Question

The test scores of a student are 56, 64, 58, 84, 73. Which of the following gives the mean deviation of the data?

• A. 8.4
• B. 7.2
• C. 9.2
• D. 9.6

Answer 1

The correct option is C 9.2

The given data set is

56, 64, 58, 84, 73

$\text{Mean deviation =}\frac{\text{sum of absolute values of deviations from mean}}{\text{number of observations}}$

Mean = $\frac{sumofalldata}{numberofdata}$

= $\frac{56+64+58+84+73}{5}$
= 67

Mean deviation is:
$\frac{|56-67|+|64-67|+|58-67|+|84-67|+|73-67|}{5}$

= $\frac{11+3+9+17+6}{5}$

= $\frac{46}{5}$

= 9.2

Hence, mean deviation of the data is 9.2