The average and standard deviation of a measurement is 15.0 ± 5.0. if 100 students measured the value, how many would you expect to get a value greater than 20?

Solution: We are given:

Using the empirical rule, we have:

covers 68% of data.

Also the percentage of values below mean = Percentage of values above mean = 50%

Now, let's find the z score for x=20

Therefore, the percentage of values greater than 1 standard deviation above mean

Expected number of students = 16% of 100 = 16

+25 = x

step-by-step explanation:

here x is the hypotenuse of a right triangle whose legs are 7 and 24.   by the pythagorean theorem, 7² + 24² must equal x²:

x² = 49 + 576 = 625.   thus, x = +√625 = +25 = x