Calculate the probability of a pizza from the sample to be a cheese pizza. Notice that there is a total of 27 pizzas in the sample, and 6 of them are cheese pizzas. Therefore, the probability of a pizza being a cheese pizza, is:
![(6)/(27)](https://img.qammunity.org/2023/formulas/mathematics/college/91ttax22ji5naj8p9jm5uymy8947ut17z9.png)
Multiply the probability times the total amount of pizzas that were sold to find the expected number of cheese pizzas that were sold:
![(6)/(27)*189=42](https://img.qammunity.org/2023/formulas/mathematics/college/be343tx7dehx2xaii6rxbmiim5qk8dho18.png)
Therefore, 42 pizzas are expected to be cheese.