Question

A set of quiz scores is shown in the histogram below. The mean of the data set is 20.2, and the (population) standard deviation is 2.4.
PLEASE PLEASE PLEASE How many numbers in the data set are within 1 standard deviation of the mean?

13
14
15
16

Answer 1

Answer:

$13$

Step-by-step explanation:

As the mean is 20.2 and the standard deviation is 2.4

The range within the first standard deviation is

(17.8,22.6)

This means that we can safely use the range of (18,22) as we cannot confirm whether the other values fall within the range.

Within this range there are

$2+3+4+3+1=13$