Answer:
Number of child tickets sold = 43
Number of adult tickets sold = 20
Step-by-step explanation:
Let the number of child ticket be c and number of adult ticket be a,
Given that the number of $8 child tickets is 17 less than 3 times the number of $12 adult tickets,
c = 3a - 17
3a - c = 17 ----------------------eqn 1
The theater received $584
That is
8 c + 12 a = 584 ----------------------eqn 2
eqn 2 /4
2 c + 3 a = 146 ----------------------eqn 3
eqn 3 - eqn 1 gives
2 c + 3 a - (3a - c) = 146 - 17
3 c = 129
c = 43
Substituting in eqn 1
3 x a - 43 = 17
3a = 60
a = 20
Number of child tickets sold = 43
Number of adult tickets sold = 20