Question

The SAT scores for a group of 10 students are shown. What is the mean absolute deviation of the group?

A. 45
B. 88
C. 880
D. 1532

Answer 1

B. 88

Explanation:

First find the mean:

Add up the values to find the mean of the data set:

1520 + 1630 + 1480 + 1580 + 1400 + 1300 + 1700 + 1610 + 1580 + 1520 = 15320

Divide 15320 by 10 because there are 10 numbers in the data set:

`(15320)/(10) = 1532`

Subtract the numbers of the data set by the mean:

1520 - 1532 = -12

1630 - 1532 = 98

1480 - 1532 = -52

1580 - 1532 = 48

1400 - 1532 = -132

1300 - 1532 = -232

1700 - 1532 = 168

1610 - 1532 = 78

1580 - 1532 = 48

1520 - 1532 = -12

The mean deviation is always positive so change the negatives to positives. After that, add them up:

12 + 98 + 52 + 48 + 132 + 232 + 168 + 78 + 48 + 12 = 880

Divide 880 by 10 because there are 10 numbers in the data set:

`(880)/(10) =88`

The mean absolute deviation is 88

Answer 2

first we have to find the mean (average) of these numbers
(1520 + 1630 + 1480 + 1580 + 1400 + 1300 + 1700 + 1610 + 1580 + 1520) / 10 = 15320 / 10 = 1532

now we find the absolute value of the difference between each data value and the mean.
|1520 - 1532| = 12
| 1630 - 1532| = 98
|1480 - 1532| = 52
|1580 - 1532| = 48
|1400 - 1532| = 132
|1300 - 1532| = 232
|1700 - 1532| = 168
|1610 - 1532| = 78
|1580 - 1532| = 48
|1520 - 1532| = 12

now, we find the mean (average) of these numbers....and that is ur MAD
(12 + 98 + 52 + 48 + 132 + 232 + 168 + 78 + 48 + 12) / 10 = 880/10 =
88 <== ur mean absolute deviation