Use the display of data to find the standard deviation.

Question

A bar graph titled Score with a horizontal axis labeled from 5 to 11 in increments of 1 and a vertical axis labeled Frequency from 0 to 12 in increments of 2 contains three vertical bars with labels and heights as follows, where the horizontal axis label is listed first and the height is listed second: 7, 12; 8, 8; 9, 12.

Score
5
6
7
8
9
10
11

Frequency
0
2
4
6
8
10
12

Answer 1

Find the mean first = sum of scores/number of scores

[(6*2)+ (7*4)...+(11*12)]/42 = ?

Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.

Standard deviation = square root of variance

I'll let you do the calculations.

Answer 2

Neat looking