Question

If 7 people appear at random to give blood, what is the probability that at least one of them is a universal donor?

a) 0.14
b) 0.28
c) 0.57
d) 0.86

Answer 1

The probability that at least one of the 7 people is a universal donor is approximately 0.6104.

Step-by-step explanation:

To find the probability that at least one of the 7 people is a universal donor, we will find the probability that none of them is a universal donor and subtract that from 1. The probability that a person is not a universal donor is 1 - 0.14 = 0.86. The probability that all 7 people are not universal donors is 0.86^7 ≈ 0.3896. So, the probability that at least one of them is a universal donor is 1 - 0.3896 ≈ 0.6104.