SOLUTION: A sample of 45 hairs are cut from a person's head. The diameter of each of the 45 hairs is measured in micrometers (μm, or in other words 10^-6m) with a mean of 38μm and

Algebra ->  Probability-and-statistics -> SOLUTION: A sample of 45 hairs are cut from a person's head. The diameter of each of the 45 hairs is measured in micrometers (μm, or in other words 10^-6m) with a mean of 38μm and       Log On


   



Question 1091773: A sample of 45 hairs are cut from a person's head. The diameter of each of the 45 hairs is measured in micrometers (μm, or in other words 10^-6m) with a mean of 38μm and a sample standard deviation of 2.306μ
If the diameters of hair are normally distributed, estimate the percentage of all hairs on this person's head that will have a diameter greater than 40.5μm.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
t=(40.5-38)/2.306
t=1.08
want the per cent of hairs greater than 40.5 given a t-distribution with df=44.
It would be 0.1430
(it would be 0.1491 with the z-distribution.)