Question

At the city museum, child admission is $5.30 and adult admission is $9.00 . On Sunday, 152 tickets were sold for a total sales of $1138.60 . How many adult tickets were sold that day?

Answer 1

the answer is 90 adult tickets 

Answer 2

90 adult tickets.
You must set up a system of equations and solve.
5.3x + 9y = 1138.6
x + y = 152

When you solve for y (adult tickets), you get 90.