Question 1177882
z=(x-mean)/sd
between 5 and 5.5 hours is a z between 1/1.25 or 0.8 and a z of 1.5/1.25=1.2
that probability for a z is 0.0968
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third quartile-find z for 0.75 probability, and that is +0.6745
0.6745=(x-4)/1.25
so x=4.84 hours at the third quartile
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this is a z>(5-4)/1.25/sqrt(4)
>1*2/1.25
z>1.6 
probability=0.0548