SOLUTION: Replacement times for Maytag washer and dryer sets are normally distributed with a mean of 4.8 years and a standard deviation of 1 years. Round all final answers to 3 decimals.

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Question 1167640: Replacement times for Maytag washer and dryer sets are normally distributed with a mean of 4.8 years and a standard deviation of 1 years.
Round all final answers to 3 decimals.
(a) Find the replacement time (in years) that separates the top 11 % from the bottom 89 %


(b) If the manufacturer wants to provide a warranty time so that only 2 % of the washer and dryer sets will be replaced before the warranty expires, what length of time (in years) would you recommend for the warranty?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
z=-1.227 is the 11th percentile.
z=(x-mean)/sd
x-mean=-1.227
x=3.573 years
This is the bottom 2%ile or z=-2.05
same formula above and it would be 2.75 years