# Need help with probability questions

## Homework Statement

Q: Approximately 16% of the calls to an airline reservation phone line result in a reservation being made.

a. Suppose that an operator handles 15 calls. What is the probability that none of the 15 calls result in a reservation? (Give the answer to 3 decimals places.)

I have tried

1-.16=.84 (incorrcect)

I thought maybe it was not probable for an answer of 0 (incorrect)

I also at one point ended up with the answer 0.011 but cannot remember how I got that answer

b.What is the probability that at least one call results in a reservation being made? (Give the answer to 3 decimals places.)

I would think you would divide 1 by 15. Probable opportunities divided by actual opportunities. But, I am sure I am supposed to use the 16% in this equation somewhere....very stuck.

## Homework Equations

I am new to this and this is my first math class in 25 years so I am not sure what to put here.

## The Attempt at a Solution

for part a:
I have tried

1-.16=.84 (incorrcect)

I thought maybe it was not probable for an answer of 0 (incorrect)

I also at one point ended up with the answer 0.011 but cannot remember how I got that answer

for part b

I would think you would divide 1 by 15. Probable opportunities divided by actual opportunities. But, I am sure I am supposed to use the 16% in this equation somewhere....very stuck.

UltrafastPED
Gold Member
The calls are independent of each other, so each call has p=0.16 for creating a reservation.

Now you queue up the calls ...

A similar, perhaps easier to grasp, problem is the following:
1. each coin flip is p=0.50 heads
2. You flip the coin 15 times
3. What is the probability that none of the coin flips is heads?

pbuk
OK, I'll help you through this just this once 