[
  "The watermelon mass is the total mass minus the papaya mass. Draw a bar model showing total = 4 1/6 and the papaya part = 1 3/8, with the watermelon as the unknown part.",
  "Convert to improper fractions with common denominator 24: 4 1/6 = 25/6 = 100/24. 1 3/8 = 11/8 = 33/24. Then 100/24 - 33/24 = 67/24.",
  "67/24 = 2 19/24 kg. Answer: 2 19/24 kg (option C)."
]