SOLUTION: The length of a certain kind of Colorado brook trout is normally distributed with a mean of 13.1 inches and a standard deviation of 1.5 inches. What minimum size limit shou

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Question 1180589: The length of a certain kind of Colorado brook trout is normally distributed with a mean of 13.1 inches and a standard deviation of 1.5 inches.

What minimum size limit should the Department of Natural Resources set if it wishes to allow people to keep 80 percent of the trout they catch?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
20th percentile is a z of -0.8416
z=(x-mean)/sd
-0.8416=(x-13.1)/1.5
-1.26=x-13.1
x=11.84 inches.