Total people = 990. Thrill rides : Family rides = 3 : 8.<br><br>
[[model:questions/solutions/q10507.png]]<br><br>
Total units = 3 + 8 = 11 units<br>
&bull; 11 units → 990<br>
&bull; 1 unit → 990 ÷ 11 = 90<br>
&bull; Thrill rides = 3 units = 3 × 90 = 270<br>
&bull; Family rides = 8 units = 8 × 90 = 720<br><br>
Now split each group into teens and adults:<br>
Thrill &mdash; teens : adults = 5 : 4<br>
&bull; Teens (thrill) = \( \frac{5}{9} \) × 270 = 150<br>
&bull; Adults (thrill) = \( \frac{4}{9} \) × 270 = 120<br>
Family &mdash; teens : adults = 2 : 7<br>
&bull; Teens (family) = \( \frac{2}{9} \) × 720 = 160<br>
&bull; Adults (family) = \( \frac{7}{9} \) × 720 = 560<br><br>
Total teens = 150 + 160 = 310<br>
Total adults = 120 + 560 = 680<br>
Adults more than teens = 680 - 310 = 370<br>
Check: 310 + 680 = 990. ✓<br><br>
Final Answer: 370