SOLUTION: For a certain type of computers, the length of time between charges of the battery is normally distributed with a mean of 51.3 hours and a standard deviation of 13.5 hours. 3% o

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Question 1136413: For a certain type of computers, the length of time between charges of the battery is normally distributed with a mean of 51.3 hours and a standard deviation of 13.5 hours.
3% of the computers have a length of time more than k hours. Find the value of k.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the 97%ile has z=+1.88
z=(x-mean)/sd
1.88=(x-51.3)/13.5
25.38=x-51.3
x=76.4 hours
or k=76.4 hours