# Statisitcs

posted by Chandler

If the student ratings of the overall effectiveness of professors is normally distributed with a mean of 5 and a standard deviation of 1.75, what proportion of the professors will be expected to be rated below 2.55?

1. MsPi_3.14159265

This is a z-score
z=(x-mu)/(standard deviation)
z=(2.55-5)/(1.75)
find z then look it up on your "areas under the curve normal distribution table" in the back of your textbook : )

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