The 78th percentile is round to two decimal places as neede

The 78^th percentile is ______ (round to two decimal places as needed.)

Assume the random variable X is normally distributed with mean sigma = 7. Find the 78th percentile. The 78th percentile is (round to two decimal places as needed.) mu = 50 and standard deviation

Solution

P(X<x)=0.78

--> P((X-mean)/s <(x-50)/7) =0.78

--> P(Z<(x-50)/7) =0.78

--> (x-50)/7 =0.77 (from standard normal table)

So x= 50+7*0.77 =55.39