Answer:
7 pepperoni pizzas
Explanation:
Where p = # of pepperoni pizzas and m = # of mushroom pizzas
124.50 = 11p + 9.5m
Now you need to guess and check:
Use this equation: (124.5 - 11 * p) / 9.5 and replace p with whole numbers until you get a whole number as the output
I got p=7 and m=5
So she bought 7 pepperoni pizzas