Question

Carly is ordering 10 pizzas for her little brother's birthday party. The ordered pizzas are either cheese, pepperoni, or both. If 8 of the pizzas have cheese on them and 5 of them have pepperoni on them, how many have both cheese and pepperoni?

Answer 1

To find out how many of the 10 pizzas ordered by Carly have both cheese and pepperoni, we can add the number of cheese pizzas (8) to the number of pepperoni pizzas (5) and subtract the total number of pizzas (10), resulting in 3 pizzas with both toppings.

Step-by-step explanation:

Carly is ordering 10 pizzas for her little brother's birthday party, with some having just cheese, some having just pepperoni, and others having both toppings. To determine how many pizzas have both cheese and pepperoni, we can use the principle of inclusion-exclusion. This principle helps us calculate the accurate number of pizzas featuring both toppings without counting them twice.

Eight of the pizzas have cheese and five have pepperoni. Adding these together gives us the total number of pizzas with either cheese or pepperoni or both, which is 8 + 5 = 13 pizzas. However, since we only have 10 pizzas, three of these pizzas have been counted twice - once in the cheese category and once in the pepperoni category because they have both toppings.

Therefore, the number of pizzas that have both cheese and pepperoni is three.