1. The length of time a customer must wait in line at the post office has approximately a normal distribution with a mean of 5.8 minutes and a standard deviation of 2.6 minutes. Find the probability that the customer will wait between 4 and 8 minutes.
2. The lifetime of a certain brand of tire follows an approximately normal distribution with a mean of 30,000 miles and a standard deviation of 4000 miles. The probability that a tire of this brand will last between 31,000 and 36,000 miles is?© BrainMass Inc. brainmass.com March 4, 2021, 7:44 pm ad1c9bdddf
The solution gives the details of calculation probability of events based on Z score and normal distribution.