Question #58874

1 Answer
Jun 11, 2017

.6826xx500=341.3 Or about 342 students

Explanation:

The question requires z-scores.

The formula is:

z=(x-mu)/sigma

Where x=the given value
mu= the mean
sigma= the standard deviation

Or

z=("your value " - " the actual mean")/(SD)

This is a bit easier to remember :)
(SD=Standard Deviation)

Plug in the values:

z=(76-82)/(6) & z=(88-82)/(6)

z=-1 & z=1

Now you look up the probability that corresponds to the z score in the table. (Which you should be provided with.)
The probability that corresponds to each z score respectfully is .1587 & .8413

You subtract .8413 from .1587 because we want to find out the scores in between these two.
Which is .6826
All you have to do now is multiply by 500.

Below is a picture that illustrates the concept better:

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