
Aron T. answered 06/04/15
Tutor
4.9
(8)
Petroleum Engineering / Calculus --- Patient Experienced Tutor
A - adult price
C - child price
3A + 4C = 136 (1)
and
2A + 3C = 97 (2)
Multiply both sides of (1) by 2:
6A + 8C = 272 (3)
Next, multiply both sides of (2) by 3:
6A + 9C = 291 (4)
Next, calculate (4) - (3):
(6-6)A +(9-8)C = (291-272) (5)
C = 19 (6)
So, the child price is $19.
Next, solve (2) for A:
2A = 97 - 3C (7)
A = (97- 3C)/2 (8)
Nest, plug in the result of (6)
A = (97 - 3(19))/2 (9)
A = (97 - 57)/2 (10)
A = 40/2 (11)
A = 20 (12)
So, the adult price is $20