2A salesman has found that the probability of a sale on a s

. 2.A salesman has found that the probability of a sale on a single contract is 0.07. If the salesman contacts 100 people,

(a) What is the probability that she will make atleast one sale?

(b) What is the expected number of sales?

(c) What is the variance of number of sales?

Solution

a) P(make alteast one sale)= 1-P(make no sale) = 1- [0.93*0.93*0.93..........100times]

                                         =0.999294