quot;On holdquot; times for callers to a local cable television company are known to be normally distributed with a standard deviation of 1.3...

"On hold" times for callers to a local cable television company are known to be normally distributed with a standard deviation of 1.3 minutes. Find the average caller "on hold" time if the company maintains that no more than 11% of callers wait more than 5.7 minutes. (Give your answer correct to two decimal places.)