Company XYZ know that replacement times for the quartz time pieces it produces are normally distributed with a mean of 17 years and a standard deviation of 1.9 years. If the company wants to provide a...

Company XYZ know that replacement times for the quartz time pieces it produces are normally distributed with a mean of 17 years and a standard deviation of 1.9 years.


If the company wants to provide a warranty so that only 1.6% of the quartz time pieces will be replaced before the warranty expires, what is the time length of the warranty?
warranty =  years