Question

The length of time a person takes to decide which shoes to purchase is normally distributed with a mean of 8.54 minutes and a standard deviation of 1.91. Find the probability that a randomly selected individual will take less than 5 minutes to select a shoe purchase. Is this outcome unusual?

Answer 1

Answer:

0.0323 = 3.23%. Is unusual

Step-by-step explanation:

Using the normal distribution we can find z value with the mean and standard deviation as follows. x is the value we want to know its probability

z = (x - mean)/standard deviation

z = (5-8.54)/1.91

z = -1.85

Using z tables for normal distribution, for z = 1.85, we have an area under the curve of 0.9677. Since we want to know the probability for 5 minutes or less, we have to substract from

p = 1- 0.9677

p = 0.0323

An event with a probability less than 5% is considered unusual.