# Need help with statistics question...

Mean height of men, mean 68 inches and a standard deviation of 2.5 inches.
What is the probability of a man selected at random will have a hight above 72 inches?
A sample of 49 meant, what is the probaility that the mean hight is greater than 67 inches (using standard score table)?

 Unknown008 Posts: 8,147, Reputation: 3745 Uber Member #2 Jan 9, 2011, 12:19 AM
By standard score table, you mean the Normal Distribution?

If so, first define your variable, that is the height.

Let X be the height of a man.

$X \sim N(68, 2.5^2)$

Then, $P(X > 75) = P(z > \frac{75 - 68}{2.5})$

Find the z-score and look up your table for the corresponding probability. Make a sketch if needed to confirm your answer.