A key metric in the cell phone industry is average revenue per user (ARPU)which represents the average dollar amount that a customer spends per store visit. Recently, AT&T reported their ARPU was $67.81. Suppose the standard deviation for this population is $18.45. What is the probability that the ARPU will be between $62 and $66 from a random sample of 35 customers?
A)0.3553
B)0.4470
C)0.5619
D)0.2496

Question

Quizplus · Accepted Answer

Using the standard normal distribution, calculate the z-scores for $62 and $66, then find the probability between these z-scores. The correct probability is approximately 0.3553.

A Key Metric in the Cell Phone Industry Is Average