can you help me arrive to a conclusion please?

Question

This data is from a sample. Calculate the mean, standard deviation, and coefficient of variation.

49.5

20.6

35.2

27.9

41.8

37.5

34.8

10.6

Please show the following answers to 2 decimal places.

Mean = 

Standard Deviation = 

Coefficient of Variation = % (Please enter a whole number.)

Answer 1

X Dev X Dev ^2 X^2

49.5 17.2625 297.9939063 2450.25

20.6 -11.6375 135.4314063 424.36

35.2 2.9625 8.77640625 1239.04

27.9 -4.3375 18.81390625 778.41

41.8 9.5625 91.44140625 1747.24

37.5 5.2625 27.69390625 1406.25

34.8 2.5625 6.56640625 1211.04

10.6 -21.6375 468.1814063 112.36

--------------------------------------------------

257.9 0 1054.89875 9368.95

MEAN AVERAGE VARIANCE STANDARD DEVIATION

32.2375 150.6998214 12.27598556

32.2375 150.6998214 12.27598556

150.6998214

Mean Average = 257.9/8 = 32.2375

THe other Mean Average was calculated by Excel formula Average()

Variance by definition = SUM of Dev^2 / (N-1)

= 1054.89875/7

variance by shortcut formula = (Sum of X^2 - N * Mean^2)/(N-1)

= ( 9368.95 - 8 * 32.2375^2) / 7

= 1054.89875/7

3rd variance was calculated by Excel formula Var()

Standard Deviation = square root ( var) = sqrt(150.6998214)

The other standard deviation was calculated by Excel formula StDev()

coefficient of variation = | stdDev / Mean |

= | 12.27598556 / 32.2375 |

= 0.38079831119585125017484195276118

this is reasonable since, 12+ / 32+ = 6/16 = 3/8 = 0.375 +