Answer: 112 children & 135 adults
Explanation:
# $
Child: x 20x
Adult: y 35y
Total: 247 6965
#: x + y = 247 → -20(x + y = 247) → -20x - 20y = -4940
$: 20x + 35y = 6965 → 1(20x + 35y = 6965) → 20x + 35y = 6965
15y = 2025
y = 135
Substitute y = 135 into either of the original equations to solve for x:
x + y = 247
x + 135 = 247
x = 112