Solving Poisson Distribution Problems: Questions on Calls/Minute

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Homework Statement

A telephone operator receives four phone calls in three minutes on the average. Let a Poisson random number X denote the number of phone calls per minute to this operator.

(a) Find the probability that this operator receives two phone calls in a minute.

(b) Find the probability that this operator receives at least two phone calls in a minute.

The Attempt at a Solution

a) lamba = (4/3)(1) = (4/3) x = 2
f(2, 4/3) = (4/3)^2 e^(-4/3)/ 2!

b) 1- [ f(0, 4/3) + f(1,4/3)]

I just want to make sure these will give me the correct answer because I must rely on the formula for the test. thank you

 

[RUber]

Homework Statement

A telephone operator receives four phone calls in three minutes on the average. Let a Poisson random number X denote the number of phone calls per minute to this operator.

(a) Find the probability that this operator receives two phone calls in a minute.

(b) Find the probability that this operator receives at least two phone calls in a minute.

The Attempt at a Solution

a) lamba = (4/3)(1) = (4/3) x = 2
f(2, 4/3) = (4/3)^2 e^(-4/3)/ 2!

b) 1- [ f(0, 4/3) + f(1,4/3)]

I just want to make sure these will give me the correct answer because I must rely on the formula for the test. thank you

Those look right to me.

 

[toothpaste666]

thank you