Answer:
Adults = 80 and 77 childs
Explanation:
Total= 157
Childs = X
Adults = Y
(Y)(3.75) + X(2.5) = 492.5
X + Y = 157 then X = 157-Y
Replacing:
3.75Y + (157 - Y)(2.5) = 492.5
3.75Y + 392.5 - 2.5Y = 492.5
1.25Y + 392.5 =492.5
1.25Y = 100
Y = 80
then
X+Y =157
X + 80 = 157
X = 77