Question

At a pizza shop, 75% of the customers order a pizza, 20% of the customers order a salad, and 15% of the customers order both a pizza and a salad. If a customer is chosen at random, what is the probability that he or she orders either a pizza or a salad?

A. 0.80
B. 0.15
C. 0.55
D. 0.95

Answer 1

The probability that a randomly chosen customer orders either a pizza or a salad is 80%, calculated using the principle of inclusion-exclusion for probabilities.

Step-by-step explanation:

The question asks for the probability that a randomly chosen customer orders either a pizza or a salad. To find this probability, we can use the principle of inclusion-exclusion for probabilities. The formula for the probability of either event A (ordering a pizza) or event B (ordering a salad) occurring is P(A or B) = P(A) + P(B) - P(A and B). In this case, P(A) is the probability of a customer ordering a pizza (75%), P(B) is the probability of ordering a salad (20%), and P(A and B) is the probability of ordering both a pizza and a salad (15%). Therefore:

P(A or B) = 0.75 + 0.20 - 0.15 = 0.80 or 80%

So the correct answer is A. 0.80.