SOLUTION: Find the indicated probabilities using the geometric​ distribution, the Poisson​ distribution, or the binomial distribution. Then determine if the events are unusual. I

Algebra ->  Probability-and-statistics -> SOLUTION: Find the indicated probabilities using the geometric​ distribution, the Poisson​ distribution, or the binomial distribution. Then determine if the events are unusual. I      Log On


   

Question 1042325: Find the indicated probabilities using the geometric​ distribution, the Poisson​ distribution, or the binomial distribution. Then determine if the events are unusual. If​ convenient, use the appropriate probability table or technology to find the probabilities.

Assume the probability that you will make a sale on any given telephone call is
0.17. Find the probability that you​ (a) make your first sale on the fifth​ call, (b) make your sale on the​ first, second, or third​ call, and​ (c) do not make a sale on the first three calls.
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Let the xth call be the call that the first sale is made. The support is then x = 1,2,3,4,5,.... .
===> Use the geometric distribution with pmf p%28x%29+=+%281-p%29%5E%28x-1%29%2Ap+=+0.83%5E%28x-1%29%2A0.17
===> (a) p%285%29+=+0.83%5E4%2A0.17+=+0.0807, to three significant figures.
(b) p%281%29+%2B+p%282%29+%2B+p%283%29+=+0.17+%2B+0.83%2A0.17+%2B+0.83%5E2%2A0.17+=+0.42821, to five significant figures.

(c) 1-p%281%29+-+p%282%29+-+p%283%29+=+1+-+0.42821+=+0.57179