Mr. McBride ordered 6 cheese pizzas and 7 pepperoni pizzas and paid $153.50 for his son's birthday party. He realized he was going to run out of pizza and made a second order. This time, he ordered 2 cheese and 2 pepperoni pizzas and paid $47.00. What is the cost of one pepperoni pizza?

Let x = cost of one cheese pizza.

Let y = cost of one pepperoni pizza.

Set up a system of equations.

6x + 7y = 153.50

2x + 2y = 47.00.

Multiply the second equation by - 3

6x + 7y = 153.50

-6x - 6y = - 141.00.

Add the equations together

y = $12.00.

Plug 12 into one of our original equations.

2x + 2 (12) = 47.

Simplify the left side.

2x + 24 = 47.

Subtract 24 from each side.

2x = 23.

Divide each side by 2

x = $11.50

In conclusion, one pepperoni pizza costs $12.00