Question

what is the mean, median, and standard deviation of the numbers 3, 7,11,12, 13, 19, 20,29, 34, and 42

Answer 1

Solution:

Given that

The mean of sample is   

x/n = (3 + 7 + 11 + 12 + 13 + 19 + 20 + 29 + 34 + 42 / 10 )

190 / 10

= 19

The sample mean is 19

The median :- Data is ascending order is as below

Median = 3,7,11,12,13,19,20,29,34,42

Middle most observation odd nuber formula

= (13 + 19 ) / 2

= 32 /2

= 16

The median is 16

Sample standard deviation is s

s = 1/(n-1)(x - )²

⁼  1/9 (3 - 19 )²+ (7 - 19 )²+ (11 - 19 )²+ (12- 19 )² +( 13 - 19 )²+ (19 - 19 )² + (20 - 19 )² + (29 - 19 )²+ (34 - 19 )²+ (42 - 19 )²)

= 1/9 (256 +144 +64+49+36+0+1+100+225 +529)

= 1404 / 9

= 156

= 12.49

Sample standard deviation is 12.49