Question

A salesperson has 65 percent chance of making a sale to a customer. The behavior of each successive customer is independent. If three customers A, B and C enter together, what is the probability that the salesperson will make a sale to at least one of the customers?

Answer 1

Change 70% to 65%

Let P(A) and P(B) be the probability that salesman sells the product to costumer A and B respectively

∴P(A)=P(B)=70%=0.7

Probability that the salesman will sell the product to customer A or B=P(A∩

B

)+P(

B

∩A)+P(A∩B)

=P(A)P(

B

)+P(

A

)P(B)+P(A)(B) ...( P(A) and P(B) are independent)

=(0.7)(1−0.7)+(1−0.7)(0.7)+(0.7)(0.7)

=0.21+0.21+0.49

=0.91