A sales representative makes a sale at approximately one-third of the businesses he calls on. On a given day, he goes to four businesses. What is the probability that he will make a sale at all four businesses?
A) $\frac { 8 } { 27 }$
B) $\frac { 2 } { 3 }$
C) $\frac { 1 } { 12 }$
D) $\frac { 1 } { 81 }$
E) $\frac { 16 } { 81 }$

Question

Quizplus · Accepted Answer

The probability of making a sale at each business is $\frac{1}{3}$, so the probability of making a sale at all four businesses is $\left(\frac{1}{3}\right)^4 = \frac{1}{81}$.

A Sales Representative Makes a Sale at Approximately One-Third of the Businesses