Question

At a pizza shop, 80% of the customers order a pizza, 15% of the customers

order a salad, and 10% 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?

Answer 1

90% out of 105% which would be 0.85

Answer 2

Answer: 0.85

Explanation:

Let A be the event that the customer orders a pizza and B be the event that the customer orders a salad.

Then , we have
`P(A)=80\%=0.80`

`P(B)=15\%=0.15`

`P(A\cap B)=10\%=0.10`

Now, the probability that he or she orders either a pizza or a salad is given by :-

`P(A\cup B)=P(A)+P(B)-P(A\cap B)\\\\\Rightarrow\ P(A\cup B)=0.80+0.15-0.10=0.85`

Hence, the required probability = 0.85