how would I write this problem in an equation?

Question

how would I write this problem in an equation.

 

A family of 4 goes to the movie theater and spends $30.50. They buy 2 tickets for children at $3.50 per ticket, 2 adult tickets, 3 boxes of popcorn at $2.50 per box. What is the cost of one adult ticket?

Answer 1

Here's what we know:

children = 2 * 3.5 = 7

popcorn = 3 * 2.5 = 7.5

adult = 2a

7 + 7.5 + 2a = 30.5

Simplify:

14.5 + 2a = 30.5

To isolate a, we start by subtracting 14.5 from both sides:

2a = 16

We then divide both sides by 2:

a = 8

 

So adult tickets cost $8.00

 

Check:

3.5 + 3.5 + 8 + 8 + 2.5 + 2.5 + 2.5 = 30.5

7 + 8 + 8 + 5 + 2.5 = 30.5

7 + 8 + 10.5 + 5 = 30.5

7 + 8 + 15.5 = 30.5

15 + 15.5 = 30.5

30.5 = 30.5