SOLUTION: assume a population with a mean of 140 and a standard deviation of 12. Find the percentile rank of a score of 147.

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Question 848990: assume a population with a mean of 140 and a standard deviation of 12.
Find the percentile rank of a score of 147.

Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
First we must standardize our variable. That is, convert to a z-score.
P[X<147] = ?
Convert to z-score.
P[Z< (147-140)/12]
P[Z< .58]
Using either a z-table or your graphing calculator:
P[Z<.58] = .719
Or 71.9th percentile.