Question

Hillary's answering machine receives about 10 telephone calls between 8 a.m. and 10 a.m. What is the probability that Hillary receives exactly one phone call between 9:00 am and 9:15 am?

Answer 1

Answer: Hillary's answering machine receives about 10 telephone calls between 8 am, and 10 a.m.

What is the probability that Hillary receives exactly one phone calls between 9:00 am and 9:15 am.

Solution:

10 telephone calls between 8 am to 10 am = 120 minutes. λ = 10

For 15 minutes, λ = (10 * 15)/120 = 1.25

P(x=1) = e^-λ * λ^x / x!

P(x=1) = e^-1.25 * 1.25^1 / 1!

P(x=1) = 0.3581

Therefore, the probability that Hillary receives exactly one phone calls between 9:00 am and 9:15 am is 0.3581.