{ "paper": { "school": "Maris Stella", "year": 2022, "level": "P4", "label": "Semestral Assessment 2", "source_prefix": "Maris Stella 2022 P4 Semestral Assessment 2", "has_answer_key": true }, "questions": [ { "n": 1, "type_id": 1, "question": "50 000 + 2000 + 90 + 8 = [?]", "answer0": "52 980", "answer1": "52 908", "answer2": "52 098", "answer3": "50 298", "correct_answer": 2, "skill_id": 105, "difficulty_id": 1, "explanation": "Add by place value: 50000 + 2000 + 90 + 8 = 52098. There are no hundreds, so the hundreds digit is 0.", "hints": ["Line up the values by place value: ten thousands, thousands, hundreds, tens, ones.", "There is no hundreds term, so put 0 in the hundreds place."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q1", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q1 = option 3 (52 098) = 0-based index 2." }, { "n": 2, "type_id": 1, "question": "56 is not a multiple of [?].", "answer0": "9", "answer1": "8", "answer2": "7", "answer3": "4", "correct_answer": 0, "skill_id": 114, "difficulty_id": 1, "explanation": "56 = 8x7 = 4x14, so 8, 7 and 4 are factors and 56 is a multiple of each. 56 / 9 is not a whole number, so 56 is not a multiple of 9.", "hints": ["A multiple of a number divides exactly with no remainder.", "Check 56 / 9 — does it give a whole number?"], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q2", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q2 = option 1 (9) = 0-based index 0." }, { "n": 3, "type_id": 1, "question": "The digit 7 in 6.017 stands for 7 [?].", "answer0": "ones", "answer1": "tenths", "answer2": "hundredths", "answer3": "thousandths", "correct_answer": 3, "skill_id": 123, "difficulty_id": 1, "explanation": "In 6.017 the places after the point are tenths (0), hundredths (1), thousandths (7). The 7 is in the third decimal place, so it stands for 7 thousandths.", "hints": ["Decimal places after the point are tenths, hundredths, thousandths.", "Count places: the 7 is the third digit after the decimal point."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q3", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q3 = option 4 (thousandths) = 0-based index 3." }, { "n": 4, "type_id": 1, "question": "Write 4 7/50 as a decimal.", "answer0": "4.75", "answer1": "4.7", "answer2": "4.14", "answer3": "4.014", "correct_answer": 2, "skill_id": 127, "difficulty_id": 2, "explanation": "7/50 = 14/100 = 0.14 (multiply numerator and denominator by 2). So 4 7/50 = 4.14.", "hints": ["Make the denominator 100: 7/50 = (7x2)/(50x2).", "14/100 = 0.14, then add the whole number 4."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q4", "image_needed": false, "image_options": false, "image_file": null, "notes": "Stem fraction is 4 and 7/50. Key Q4 = option 3 (4.14) = 0-based index 2." }, { "n": 5, "type_id": 1, "question": "Which one of the following has 1/6 of the figure shaded?", "answer0": "Figure 1", "answer1": "Figure 2", "answer2": "Figure 3", "answer3": "Figure 4", "correct_answer": 1, "skill_id": 120, "difficulty_id": 2, "explanation": "A bar divided into 6 equal parts with exactly 1 part shaded shows 1/6. Figure 2 has 6 equal strips with 1 strip shaded, so 1/6 is shaded.", "hints": ["The figure must be split into 6 equal parts.", "Exactly one of those six parts should be shaded."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q5", "image_needed": true, "image_options": true, "image_file": null, "image_page": 4, "image_bbox": [0.22, 0.16, 0.72, 0.28], "image_loc": "row of four shaded bar figures below the question, near top of page", "notes": "Image-option MCQ: four bar diagrams labelled (1)-(4). Key Q5 = option 2 = 0-based index 1. Crop each option to q5_opt0..q5_opt3." }, { "n": 6, "type_id": 1, "question": "9 3/4 = [?]/4\nWhat is the missing number in the box?", "answer0": "27", "answer1": "33", "answer2": "36", "answer3": "39", "correct_answer": 3, "skill_id": 119, "difficulty_id": 2, "explanation": "Convert the mixed number to an improper fraction: 9 3/4 = (9x4 + 3)/4 = (36 + 3)/4 = 39/4. So the missing numerator is 39.", "hints": ["Multiply the whole number by the denominator, then add the numerator.", "9 x 4 = 36, then 36 + 3 = 39."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q6", "image_needed": false, "image_options": false, "image_file": null, "notes": "Question is 9 and 3/4 = box/4. Key Q6 = option 4 (39) = 0-based index 3." }, { "n": 7, "type_id": 1, "question": "The perimeter of the rectangle is 40 cm. Its breadth is 8 cm. Find its length.", "answer0": "5 cm", "answer1": "12 cm", "answer2": "16 cm", "answer3": "24 cm", "correct_answer": 1, "skill_id": 136, "difficulty_id": 2, "explanation": "Perimeter = 2 x (length + breadth). 40 = 2 x (length + 8), so length + 8 = 20, length = 12 cm.", "hints": ["Half the perimeter equals length + breadth: 40 / 2 = 20.", "Subtract the breadth: 20 - 8 = 12 cm."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q7", "image_needed": true, "image_options": false, "image_file": "q7.png", "image_page": 4, "image_bbox": [0.39, 0.66, 0.63, 0.79], "image_loc": "rectangle diagram in middle of page showing breadth 8 cm and Perimeter = 40 cm", "notes": "Key Q7 = option 2 (12 cm) = 0-based index 1." }, { "n": 8, "type_id": 1, "question": "Four letters are shown on a square grid. How many letters have at least one line of symmetry?", "answer0": "1", "answer1": "2", "answer2": "3", "answer3": "4", "correct_answer": 1, "skill_id": 145, "difficulty_id": 2, "explanation": "Inspect each of the four block letters on the grid. Two of them have at least one line of symmetry. Answer: 2.", "hints": ["A line of symmetry folds the letter so the two halves match exactly.", "Check each letter individually for a vertical or horizontal fold line."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q8", "image_needed": true, "image_options": false, "image_file": "q8.png", "image_page": 5, "image_bbox": [0.33, 0.17, 0.74, 0.32], "image_loc": "square grid with four letters drawn on it, below the question near top of page", "notes": "Key Q8 = option 2 (2) = 0-based index 1." }, { "n": 9, "type_id": 1, "question": "Matthew and Paul had $348 altogether. After Paul gave $33 to Matthew, they each had an equal amount of money. How much did Paul have at first?", "answer0": "$141", "answer1": "$174", "answer2": "$207", "answer3": "$282", "correct_answer": 2, "skill_id": 118, "difficulty_id": 2, "explanation": "Total stays $348, so after giving each has 348 / 2 = $174. Paul gave away $33, so at first Paul had 174 + 33 = $207.", "hints": ["Equal share = total / 2 = 348 / 2 = 174.", "Paul lost $33 to reach 174, so add it back: 174 + 33."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q9", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q9 = option 3 ($207) = 0-based index 2." }, { "n": 10, "type_id": 1, "question": "How many 4-digit numbers which are smaller than 5000 can be formed using the digits 9, 3, 7 and 0?", "answer0": "18", "answer1": "12", "answer2": "3", "answer3": "6", "correct_answer": 3, "skill_id": 105, "difficulty_id": 3, "explanation": "For a number below 5000 the thousands digit must be 3 (0 not allowed as leading digit; 9 and 7 are too big). The remaining 3 digits (9, 7, 0) can be arranged in 3 x 2 x 1 = 6 ways. So 6 numbers.", "hints": ["The first digit must be less than 5 and cannot be 0, so it must be 3.", "Arrange the other three digits: 3 x 2 x 1 = 6."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q10", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q10 = option 4 (6) = 0-based index 3." }, { "n": 11, "type_id": 1, "question": "What is the value of the reading at X?", "answer0": "10.02", "answer1": "10.04", "answer2": "10.2", "answer3": "10.4", "correct_answer": 1, "skill_id": 124, "difficulty_id": 2, "explanation": "Between 10.0 and the next labelled mark each small interval is 0.02 (5 intervals per 0.1). X is 2 intervals past 10.0, so 10.0 + 2 x 0.02 = 10.04.", "hints": ["Work out the size of one small interval between the labelled values.", "Each gap of 0.1 is split into 5 parts, so each part is 0.02."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q11", "image_needed": true, "image_options": false, "image_file": "q11.png", "image_page": 6, "image_bbox": [0.17, 0.16, 0.86, 0.27], "image_loc": "horizontal number line marked 9.7, 9.8, 9.9, 10.0 with arrow pointing to X, below the question", "notes": "Key Q11 = option 2 (10.04) = 0-based index 1." }, { "n": 12, "type_id": 1, "question": "The following figure is made up of a square and a rectangle. The area of the square is 36 cm². What is the length of AB?", "answer0": "6 cm", "answer1": "9 cm", "answer2": "18 cm", "answer3": "21 cm", "correct_answer": 2, "skill_id": 138, "difficulty_id": 2, "explanation": "The square has area 36 cm², so its side = 6 cm (6 x 6 = 36). AB = square side + rectangle length = 6 + 12 = 18 cm.", "hints": ["Side of the square = square root of its area: sqrt(36) = 6.", "AB spans the square (6 cm) and the rectangle (12 cm): 6 + 12."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q12", "image_needed": true, "image_options": false, "image_file": "q12.png", "image_page": 6, "image_bbox": [0.33, 0.51, 0.66, 0.66], "image_loc": "figure of a square (area 36 cm2) joined to a rectangle (12 cm), labelled A B C D, middle of page", "notes": "Key Q12 = option 3 (18 cm) = 0-based index 2." }, { "n": 13, "type_id": 1, "question": "When a container is half-filled with water, it weighs 1.32 kg. When the container is completely filled with water, it weighs 2.1 kg. How heavy is the empty container?", "answer0": "0.1 kg", "answer1": "0.21 kg", "answer2": "0.54 kg", "answer3": "0.78 kg", "correct_answer": 2, "skill_id": 131, "difficulty_id": 2, "explanation": "Half the water adds 2.1 - 1.32 = 0.78 kg, so a full load of water is 2 x 0.78 = 1.56 kg. Empty container = 2.1 - 1.56 = 0.54 kg.", "hints": ["Going from half-full to full adds the second half of the water: 2.1 - 1.32 = 0.78 kg.", "Full water = 2 x 0.78; subtract from the full weight to get the empty container."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q13", "image_needed": true, "image_options": false, "image_file": "q13.png", "image_page": 7, "image_bbox": [0.31, 0.18, 0.80, 0.37], "image_loc": "three containers (half-filled 1.32 kg, full 2.1 kg, empty ?) below the question", "notes": "Key Q13 = option 3 (0.54 kg) = 0-based index 2." }, { "n": 14, "type_id": 1, "question": "The table shows the duration of different activities held at the community club.\nLisa started an activity at 10 35 and ended at 12 10. Which activity did she participate at the community club?", "answer0": "Cupcake decorating", "answer1": "Candle making", "answer2": "Wushu", "answer3": "Speech and drama", "correct_answer": 2, "skill_id": 135, "difficulty_id": 2, "explanation": "From 10 35 to 12 10 is 1 h 35 min (10 35 to 11 35 is 1 h, then 35 min more to 12 10). The table shows Wushu lasts 1 h 35 min, so she did Wushu.", "hints": ["Find the duration from 10 35 to 12 10.", "10 35 + 1 h = 11 35, then to 12 10 is 35 min more, so 1 h 35 min — match it in the table."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q14", "image_needed": true, "image_options": false, "image_file": "q14.png", "image_page": 7, "image_bbox": [0.27, 0.59, 0.73, 0.74], "image_loc": "two-column table (Activity / Duration) in middle of page", "notes": "Durations: Cupcake decorating 35 min, Candle making 1 h 25 min, Wushu 1 h 35 min, Speech and drama 2 h 25 min. Key Q14 = option 3 (Wushu) = 0-based index 2." }, { "n": 15, "type_id": 1, "question": "Min Jie is standing at point Y and facing South-east. He turns 225° anti-clockwise, then he makes a 3/4 - turn in a clockwise direction. Which direction is he facing in the end?", "answer0": "North", "answer1": "South", "answer2": "East", "answer3": "West", "correct_answer": 1, "skill_id": 142, "difficulty_id": 3, "explanation": "Start facing South-east. Turning 225° anti-clockwise (225 / 45 = 5 eighth-turns) lands on North-west. A 3/4 turn clockwise = 270° clockwise = 6 eighth-turns clockwise from North-west, which lands on South. He faces South.", "hints": ["Each compass point is 45° apart; 225° anti-clockwise is 5 steps anti-clockwise.", "A 3/4 turn is 270° (6 compass points). Apply it clockwise from where you ended up."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q15", "image_needed": true, "image_options": false, "image_file": "q15.png", "image_page": 8, "image_bbox": [0.24, 0.23, 0.79, 0.48], "image_loc": "8-point compass diagram centred on point Y, below the question", "notes": "Key Q15 = option 2 (South) = 0-based index 1." }, { "n": 16, "type_id": 1, "question": "The figure shows a square ABCD. ∠ABE = 33° and ∠x is twice of ∠y.\nFind ∠x.", "answer0": "19°", "answer1": "22°", "answer2": "38°", "answer3": "57°", "correct_answer": 2, "skill_id": 139, "difficulty_id": 3, "explanation": "∠ABC of the square is 90°. So ∠ABE + ∠x + ∠y = 90°: 33 + x + y = 90, giving x + y = 57. With x = 2y, 3y = 57, y = 19°, so x = 38°.", "hints": ["The corner of a square is 90°, made up of 33° + ∠x + ∠y.", "x + y = 57 and x = 2y, so 3y = 57."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q16", "image_needed": true, "image_options": false, "image_file": "q16.png", "image_page": 9, "image_bbox": [0.33, 0.16, 0.70, 0.41], "image_loc": "square ABCD with lines from B creating angles 33°, x, y at corner B, below the question", "notes": "Key Q16 = option 3 (38°) = 0-based index 2." }, { "n": 17, "type_id": 1, "question": "Given the line of symmetry, what is the least number of squares that must be shaded to complete the symmetric figure?", "answer0": "5", "answer1": "6", "answer2": "3", "answer3": "4", "correct_answer": 0, "skill_id": 145, "difficulty_id": 3, "explanation": "Reflect each already-shaded square across the diagonal line of symmetry. The squares whose mirror image is not yet shaded must be added. Counting these gives 5 squares.", "hints": ["For each shaded square, find its mirror image across the diagonal line.", "Count only the mirror squares that are still blank."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q17", "image_needed": true, "image_options": false, "image_file": "q17.png", "image_page": 9, "image_bbox": [0.39, 0.66, 0.62, 0.83], "image_loc": "grid of squares with a diagonal line of symmetry and several shaded cells, below the question", "notes": "Key Q17 = option 1 (5) = 0-based index 0." }, { "n": 18, "type_id": 1, "question": "Dean has to walk one step to the East and three steps to the North to reach Point A. Where is he now?", "answer0": "E", "answer1": "B", "answer2": "C", "answer3": "D", "correct_answer": 0, "skill_id": 142, "difficulty_id": 2, "explanation": "To reach A he goes 1 step East and 3 steps North. So his current position is 1 step West and 3 steps South of A. From A, going 1 left and 3 down lands on point E.", "hints": ["Work backwards from A: reverse the moves (1 step West and 3 steps South).", "On the grid, count 1 column left and 3 rows down from A."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q18", "image_needed": true, "image_options": false, "image_file": "q18.png", "image_page": 10, "image_bbox": [0.27, 0.16, 0.62, 0.55], "image_loc": "grid with points A, B, C, D, E marked and a North arrow to its right, below the question", "notes": "Key Q18 = option 1 (E) = 0-based index 0." }, { "n": 19, "type_id": 1, "question": "The bar graph shows the number of card games sold from Jan to Jun.\nIn which 2 months were the sum of the number of card games sold the same as the number of card games sold in March?", "answer0": "Apr and May", "answer1": "Feb and May", "answer2": "Jan and Apr", "answer3": "Jan and Jun", "correct_answer": 2, "skill_id": 146, "difficulty_id": 2, "explanation": "From the graph March = 90. Jan (about 40) + Apr (about 50) = 90, matching March. So the answer is Jan and Apr.", "hints": ["Read March's bar height first.", "Find two months whose bar heights add up to March's value."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q19", "image_needed": true, "image_options": false, "image_file": "q19.png", "image_page": 11, "image_bbox": [0.20, 0.18, 0.82, 0.46], "image_loc": "vertical bar graph (Number of card games sold, Jan-Jun), top of page", "notes": "Shared bar graph for Q19 and Q20. Bars approx: Jan 40, Feb 65, Mar 90, Apr 50, May 35, Jun 45. Key Q19 = option 3 (Jan and Apr) = 0-based index 2." }, { "n": 20, "type_id": 1, "question": "The bar graph shows the number of card games sold from Jan to Jun.\nThe price of a set of card game was $48. How much money was collected from all the card games sold in May?", "answer0": "$384", "answer1": "$1440", "answer2": "$1680", "answer3": "$1920", "correct_answer": 2, "skill_id": 118, "difficulty_id": 2, "explanation": "From the graph, 35 card games were sold in May. Money collected = 35 x $48 = $1680.", "hints": ["Read May's bar height from the graph (35).", "Multiply the number sold by the price: 35 x 48."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q20", "image_needed": true, "image_options": false, "image_file": "q20.png", "image_page": 11, "image_bbox": [0.20, 0.18, 0.82, 0.46], "image_loc": "vertical bar graph (Number of card games sold, Jan-Jun), top of page (same graph as Q19)", "notes": "May = 35 sold. Key Q20 = option 3 ($1680) = 0-based index 2." }, { "n": 21, "type_id": 2, "question": "Round off 89 641 to the nearest hundred.", "answer0": "89 600", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 109, "difficulty_id": 1, "explanation": "The tens digit is 4 (less than 5), so round down: 89 641 rounds to 89 600.", "hints": ["Look at the tens digit to decide rounding to the nearest hundred.", "Tens digit 4 is below 5, so keep the hundreds digit and make the rest 0."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q21", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q21 = 89600." }, { "n": 22, "type_id": 2, "question": "Subtract 536 from 822.", "answer0": "286", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 116, "difficulty_id": 1, "explanation": "822 - 536 = 286.", "hints": ["\"Subtract 536 from 822\" means 822 - 536.", "Use column subtraction with regrouping."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q22", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q22 = 286." }, { "n": 23, "type_id": 2, "question": "Find the product of 2106 and 8.", "answer0": "16 848", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 116, "difficulty_id": 1, "explanation": "2106 x 8 = 16 848.", "hints": ["\"Product\" means multiply: 2106 x 8.", "Multiply each digit: 8 x 2106 = 16848."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q23", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q23 = 16848." }, { "n": 24, "type_id": 2, "question": "Arrange the following numbers in order from the greatest to the smallest.\n1.207, 1.027, 1.702\nGreatest: [?] , [?] , [?] Smallest", "answer0": "1.702", "answer1": "1.207", "answer2": "1.027", "answer3": null, "correct_answer": null, "skill_id": 124, "difficulty_id": 2, "explanation": "Compare digit by digit after the decimal point: 1.702 has 7 tenths (largest), then 1.207 has 2 tenths, then 1.027 has 0 tenths. Greatest to smallest: 1.702, 1.207, 1.027.", "hints": ["Compare the tenths digit first, then hundredths, then thousandths.", "Larger tenths means larger number: 7 > 2 > 0."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q24", "image_needed": false, "image_options": false, "image_file": null, "notes": "Ordering FIB, three blanks in order greatest->smallest. Key Q24 = 1.702, 1.207, 1.027." }, { "n": 25, "type_id": 2, "question": "18.07 + 0.96 = [?]", "answer0": "19.03", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 129, "difficulty_id": 1, "explanation": "Line up the decimal points: 18.07 + 0.96 = 19.03.", "hints": ["Align the decimal points before adding.", "0.07 + 0.96 = 1.03, carry to the whole number part."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q25", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q25 = 19.03." }, { "n": 26, "type_id": 2, "question": "3/8 = 15/[?]\nWhat is the missing number in the box?", "answer0": "40", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 119, "difficulty_id": 1, "explanation": "The numerator goes from 3 to 15, which is x5. Multiply the denominator by 5 too: 8 x 5 = 40. So 3/8 = 15/40.", "hints": ["Find what the numerator was multiplied by: 3 x ? = 15.", "Multiply the denominator by the same number: 8 x 5."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q26", "image_needed": false, "image_options": false, "image_file": null, "notes": "Question is 3/8 = 15/box. Key Q26 = 40." }, { "n": 27, "type_id": 2, "question": "What is the value of 11/12 + 1/4? Express your answer as a mixed number.", "answer0": "1 2/12", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 121, "difficulty_id": 2, "explanation": "Make a common denominator of 12: 1/4 = 3/12. Then 11/12 + 3/12 = 14/12 = 1 2/12. (The answer key leaves it as 1 2/12.)", "hints": ["Convert 1/4 to twelfths: 1/4 = 3/12.", "Add: 11/12 + 3/12 = 14/12, then write as a mixed number."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q27", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q27 = 1 2/12 (not simplified in the key). Equivalent simplest mixed number is 1 1/6." }, { "n": 28, "type_id": 1, "question": "In the figure, one of the lines is parallel to DE. Which line is parallel to DE?", "answer0": "AF", "answer1": "BG", "answer2": "CH", "answer3": "AB", "correct_answer": 1, "skill_id": 143, "difficulty_id": 2, "explanation": "Comparing the lines in the figure against DE, line BG runs in the same direction as DE without meeting it. So BG is parallel to DE.", "hints": ["Parallel lines never meet and keep the same slope.", "Compare each line's direction with DE in the figure."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q28", "image_needed": true, "image_options": false, "image_file": "q28.png", "image_page": 17, "image_bbox": [0.28, 0.16, 0.50, 0.30], "image_loc": "quadrilateral figure with points A, F, B, G, H, C, E, D and internal lines, top-left of question", "notes": "Originally a free-response naming task; converted to MCQ with the candidate lines as options (BG correct). Key Q28 = BG = 0-based index 1." }, { "n": 29, "type_id": 1, "question": "In the figure, name the two angles that are smaller than 90°.", "answer0": "∠a and ∠e", "answer1": "∠b and ∠c", "answer2": "∠c and ∠d", "answer3": "∠d and ∠f", "correct_answer": 0, "skill_id": 140, "difficulty_id": 2, "explanation": "An acute angle is smaller than 90°. In the figure, angles a and e are the two acute (less than 90°) angles.", "hints": ["Angles smaller than 90° are acute — they look 'sharp'.", "Inspect each marked angle in the figure and pick the two that are clearly less than a right angle."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q29", "image_needed": true, "image_options": false, "image_file": "q29.png", "image_page": 17, "image_bbox": [0.27, 0.37, 0.52, 0.58], "image_loc": "irregular pentagon with marked angles a, b, c, d, e, f, below the question", "notes": "Originally free-response (name two angles); converted to MCQ. Word/letter answer so MCQ per spec. Key Q29 = angles a and e = 0-based index 0." }, { "n": 30, "type_id": 2, "question": "Tom watched a movie. The movie lasted 1 h 55 min. The movie ended at 00 20. What time did it start? Give your answer in 24-hour clock.", "answer0": "2225", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 135, "difficulty_id": 2, "explanation": "Work backwards from 00 20 by 1 h 55 min. 00 20 minus 1 h = 23 20 (previous day); minus 55 min more = 22 25. The movie started at 2225.", "hints": ["Subtract the duration from the end time, going back past midnight.", "00 20 - 1 h = 23 20, then - 55 min = 22 25."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q30", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q30 = 2225 (22 25 in 24-hour clock)." }, { "n": 31, "type_id": 2, "question": "Two factors of 39 are 1 and 39. What is the sum of all the factors of 39?", "answer0": "56", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 111, "difficulty_id": 2, "explanation": "The factors of 39 are 1, 3, 13 and 39. Their sum = 1 + 3 + 13 + 39 = 56.", "hints": ["List all factor pairs of 39: 1x39 and 3x13.", "Add every factor: 1 + 3 + 13 + 39."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q31", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q31 = 56." }, { "n": 32, "type_id": 2, "question": "The figure is made up of 5 identical squares. The side of each square is 6 cm. What is the perimeter of the figure?\n[?] cm", "answer0": "84", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 138, "difficulty_id": 3, "explanation": "Trace the outline of the cross/T-shaped figure of 5 squares. Counting the exposed unit edges around the boundary gives 14 sides of 6 cm. Perimeter = 14 x 6 = 84 cm.", "hints": ["Perimeter is the total length around the outside of the whole figure.", "Count the exposed 6 cm edges on the boundary, then multiply by 6."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q32", "image_needed": true, "image_options": false, "image_file": "q32.png", "image_page": 18, "image_bbox": [0.27, 0.36, 0.46, 0.52], "image_loc": "arrangement of 5 identical squares (each side 6 cm) below the question", "notes": "Answer is in cm. Key Q32 = 84 cm." }, { "n": 33, "type_id": 2, "question": "The third multiple of a 1-digit number is 35 less than its eighth multiple. What is the 1-digit number?", "answer0": "7", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 114, "difficulty_id": 2, "explanation": "8th multiple minus 3rd multiple = 5 of the number. This equals 35, so the number = 35 / 5 = 7.", "hints": ["Eighth multiple is 8n, third multiple is 3n; their difference is 5n.", "5n = 35, so n = 7."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q33", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q33 = 7." }, { "n": 34, "type_id": 2, "question": "The figure is made up of squares of 2 different sizes.\nWhat is the length of XY?\n[?] m", "answer0": "27", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 138, "difficulty_id": 3, "explanation": "The big square has side 18 m (the marked height). The three small squares each have side 18 / 2 = 9 m... using the figure proportions, XY = 27 m as per the answer key.", "hints": ["The 18 m height gives the side of the larger square.", "Add up the side lengths along the base XY."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q34", "image_needed": true, "image_options": false, "image_file": "q34.png", "image_page": 19, "image_bbox": [0.27, 0.13, 0.62, 0.32], "image_loc": "staircase figure of squares of two sizes, marked 18 m on the right and XY along the base, top of page", "notes": "Answer in m. Key Q34 = 27 m." }, { "n": 35, "type_id": 2, "question": "Ron's mass is 39.8 kg. He is 27.35 kg lighter than his father. What is their total mass?\n[?] kg", "answer0": "106.95", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 131, "difficulty_id": 2, "explanation": "Father's mass = 39.8 + 27.35 = 67.15 kg. Total mass = 39.8 + 67.15 = 106.95 kg.", "hints": ["Find the father's mass first: Ron + 27.35.", "Add Ron's mass and the father's mass for the total."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q35", "image_needed": false, "image_options": false, "image_file": null, "notes": "Answer in kg. Key Q35 = 106.95 kg." }, { "n": 36, "type_id": 2, "question": "The length of a metal rod is 167.8 cm when rounded to 1 decimal place. What is the least possible length of the rod? Give your answer to 2 decimal places.\n[?] cm", "answer0": "167.75", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 128, "difficulty_id": 3, "explanation": "Lengths from 167.75 up to (but below) 167.85 round to 167.8 (1 d.p.). The least value that rounds up to 167.8 is 167.75 cm.", "hints": ["Find the range of values that round to 167.8 at 1 decimal place.", "The smallest such value is the lower boundary: 167.75."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q36", "image_needed": false, "image_options": false, "image_file": null, "notes": "Answer in cm to 2 d.p. Key Q36 = 167.75 cm." }, { "n": 37, "type_id": 0, "question": "The table shows the amount of old newspapers collected by 4 classes over one week. For each statement, state whether it is True, False or Not possible to tell.\n(a) The girls collected less amount of old newspapers than the boys.\n(b) The least amount would be collected by 6B if this activity continued for another week.", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 146, "difficulty_id": 2, "explanation": "(a) Boys total = 24+14+45+32 = 115 kg; Girls total = 20+11+13+25 = 69 kg. Girls < boys, so TRUE. (b) Future collection cannot be predicted from one week's data, so NOT POSSIBLE TO TELL.", "hints": ["For (a), add up all the boys' values and all the girls' values and compare.", "For (b), ask whether one week of data can predict next week."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q37", "image_needed": true, "image_options": false, "image_file": "q37.png", "image_page": 20, "image_bbox": [0.28, 0.14, 0.74, 0.30], "image_loc": "table of newspapers collected (Class / Boys / Girls) at top of question", "notes": "type_id 0: tick-the-column (True/False/Not possible to tell) format has no app question type, so skipped on insert. Key Q37 = (a) True, (b) Not possible to tell." }, { "n": 38, "type_id": 2, "question": "The figure is made up of 16 identical rectangles. What fraction of the figure is shaded? Express your answer in the simplest form.", "answer0": "1/4", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 120, "difficulty_id": 2, "explanation": "The shaded triangular regions together cover the equivalent of 4 of the 16 rectangles. 4/16 = 1/4 in simplest form.", "hints": ["Work out the shaded area as a number of whole rectangles.", "Write shaded over total (out of 16) and simplify."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q38", "image_needed": true, "image_options": false, "image_file": "q38.png", "image_page": 20, "image_bbox": [0.19, 0.62, 0.50, 0.78], "image_loc": "grid of 16 identical rectangles with shaded triangular regions, below the question", "notes": "Answer is a fraction in simplest form. Key Q38 = 1/4." }, { "n": 39, "type_id": 1, "question": "The line graph shows Mr David's mass from Jun to Dec.\nDuring which 1-month interval did Mr David lose the most mass?", "answer0": "From Jun to Jul", "answer1": "From Aug to Sep", "answer2": "From Oct to Nov", "answer3": "From Nov to Dec", "correct_answer": 1, "skill_id": 146, "difficulty_id": 2, "explanation": "The steepest downward segment of the line graph is between Aug and Sep, where the mass drops the most in one month. So the answer is from Aug to Sep.", "hints": ["The biggest drop is the steepest part of the line.", "Compare the height fall of each one-month segment."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q39", "image_needed": true, "image_options": false, "image_file": "q39.png", "image_page": 21, "image_bbox": [0.13, 0.18, 0.82, 0.46], "image_loc": "line graph of Mass (kg) vs months Jun-Dec, top of page", "notes": "Originally fill-in (From ___ to ___); converted to MCQ. Shared graph with Q40. Key Q39 = Aug to Sep = 0-based index 1." }, { "n": 40, "type_id": 2, "question": "The line graph shows Mr David's mass from Jun to Dec.\nHow much mass did Mr David lose altogether in the 7 months?\n[?] kg", "answer0": "22", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 146, "difficulty_id": 2, "explanation": "Read the starting mass in Jun (about 94 kg) and the ending mass in Dec (about 72 kg). Loss = 94 - 72 = 22 kg.", "hints": ["Read the mass at the first point (Jun) and the last point (Dec).", "Subtract the final mass from the starting mass."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q40", "image_needed": true, "image_options": false, "image_file": "q40.png", "image_page": 21, "image_bbox": [0.13, 0.18, 0.82, 0.46], "image_loc": "line graph of Mass (kg) vs months Jun-Dec, top of page (same graph as Q39)", "notes": "Answer in kg. Key Q40 = 22 kg." }, { "n": 41, "type_id": 2, "question": "An egg seller had 36 boxes of eggs. Each box contained 30 eggs. 82 eggs were broken and thrown away. The remaining eggs were repacked into cartons of 8 eggs each.\n(a) How many eggs were unbroken?\n(b) How many eggs were not packed into the cartons?", "answer0": "998", "answer1": "6", "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 118, "difficulty_id": 2, "explanation": "(a) Total eggs = 36 x 30 = 1080. Unbroken = 1080 - 82 = 998. (b) 998 / 8 = 124 remainder 6, so 124 full cartons and 6 eggs left over (not packed).", "hints": ["(a) Total = 36 x 30, then subtract the 82 broken eggs.", "(b) Divide the unbroken eggs by 8; the remainder is the eggs not packed."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q41", "image_needed": false, "image_options": false, "image_file": null, "notes": "Two-blank FIB: answer0 = (a) 998, answer1 = (b) 6. Key Q41 a)998 b)6." }, { "n": 42, "type_id": 2, "question": "Terry had $392 and Willy had $47 at first. Their father gave each of them an equal amount of money. In the end, Terry had 6 times as much money as Willy. How much money did their father give to each of them?", "answer0": "$22", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 118, "difficulty_id": 3, "explanation": "Let each receive g. Then 392 + g = 6 x (47 + g). 392 + g = 282 + 6g, so 110 = 5g, g = $22. (Check: Terry 392+22=414, Willy 47+22=69, 414 = 6 x 69.)", "hints": ["Add the same amount g to each: Terry = 392 + g, Willy = 47 + g.", "Set Terry = 6 x Willy and solve: 392 + g = 6(47 + g)."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q42", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key Q42 = $22." }, { "n": 43, "type_id": 2, "question": "Mrs Lim bought some papayas and 12 mangoes. The offer is: 1 mango for $4.20; Buy 2 mangoes, get 1 mango free!\n(a) How much did Mrs Lim pay for the 12 mangoes?\n(b) Mrs Lim paid the cashier $100 for all the fruits and received $40.80 change. How much did all the fruits cost?", "answer0": "$33.60", "answer1": "$59.20", "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 131, "difficulty_id": 3, "explanation": "(a) Buy 2 get 1 free means every 3 mangoes she pays for 2. For 12 mangoes she pays for 12 / 3 x 2 = 8 mangoes: 8 x $4.20 = $33.60. (b) All fruits cost = $100 - $40.80 = $59.20.", "hints": ["(a) In each group of 3 mangoes only 2 are charged; 12 mangoes = 4 groups, so pay for 8.", "(b) Cost = amount paid minus change: 100 - 40.80."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q43", "image_needed": true, "image_options": false, "image_file": "q43.png", "image_page": 24, "image_bbox": [0.25, 0.16, 0.72, 0.34], "image_loc": "drawing of mangoes with a starburst offer label (1 mango for $4.20; Buy 2 mangoes, get 1 mango free), top of question", "notes": "Two-blank FIB: answer0 = (a) $33.60, answer1 = (b) $59.20. Offer text carried into stem. Key Q43 a)$33.60 b)$59.20." }, { "n": 44, "type_id": 2, "question": "A baker baked 3 types of cakes. 1/3 of the cakes were chocolate cakes, 2/9 of them were blueberry cakes and the remaining were butter cakes.\n(a) What fraction of the cakes were butter cakes?\n(b) A total of 108 cakes were baked. Each cake was sold at $15. How much money was collected when 1/4 of the cakes baked were sold?", "answer0": "4/9", "answer1": "$405", "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 122, "difficulty_id": 3, "explanation": "(a) Chocolate + blueberry = 1/3 + 2/9 = 3/9 + 2/9 = 5/9. Butter = 1 - 5/9 = 4/9. (b) 1/4 of 108 = 27 cakes sold. Money = 27 x $15 = $405.", "hints": ["(a) Add the chocolate and blueberry fractions (common denominator 9), then subtract from 1.", "(b) Find 1/4 of 108, then multiply by $15."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q44", "image_needed": false, "image_options": false, "image_file": null, "notes": "Two-blank FIB: answer0 = (a) 4/9, answer1 = (b) $405. Key Q44 a)4/9 b)$405." }, { "n": 45, "type_id": 2, "question": "A square and a rectangle were cut out from a piece of rectangular paper. The area of the rectangle that was cut out is 18 cm².\nFind the length of the rectangular paper.\n[?] cm", "answer0": "24", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 136, "difficulty_id": 3, "explanation": "The cut-out rectangle has area 18 cm² and one side (width) 3 cm, so its length = 18 / 3 = 6 cm. Reading the marked horizontal segments along the top: 3 + (square width) + 5 + 3 + ... summing the labelled lengths across the paper gives a total length of 24 cm.", "hints": ["First find the missing side of the cut-out rectangle: area / known side = 18 / 3.", "Add up all the marked horizontal lengths across the top of the paper."], "source": "Maris Stella 2022 P4 Semestral Assessment 2 Q45", "image_needed": true, "image_options": false, "image_file": "q45.png", "image_page": 26, "image_bbox": [0.17, 0.18, 0.64, 0.40], "image_loc": "rectangular paper with a square and a rectangle cut out, marked 3 cm, 5 cm, 15 cm dimensions and ? for the length, top-left of page", "notes": "Answer in cm. Key Q45 = 24 cm." } ] }