SOLUTION: The amount of time that office workers at Company XYZ spend on the computer each workday is normally distributed with a mean of 3.1 hours and a standard deviation of 0.5 hours. Fi

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Question 869231: The amount of time that office workers at Company XYZ spend on the computer each workday is normally distributed with a mean of 3.1 hours and a standard deviation of 0.5 hours. Find the percentage of office workers at Company XYZ who spend less than 4.1 hours on the computer per workday.
(a) 97.72% (b) 65.00% (c) 95.00% (d) 99.70%
I have: %28x-mean%29%2F%28standard+deviation%2Fsquare+root+of+n%29
4.1 - 3.1= 1/.5 = 2. Looked up in the back of chart E (Standard deviation) and got .9772 turned into percent would be 97.72%, correct?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
z = (x-mu)/sigma
z = (4.1-3.1)/0.5
z = 1/0.5
z = 2


Now use a table to find the area to the left of z = 2. This is approximately 0.9772 (roughly 97.72%)

So you are correct. The only typo you made was writing %28x-mean%29%2F%28standard+deviation%2Fsquare+root+of+n%29 when you should have written %28x-mu%29%2Fsigma

mu+=+mean (greek letter lowercase mu)
sigma+=+standard_deviation (greek letter lowercase sigma)