Answer:
a) Mean = $121
Sum of deviations = $0
b) Standard deviation = 41.19
Variance = 1696.67
Range = $120
Step-by-step explanation:
We are given the following data:
$91 , $176 , $108 , $115 , $56 , $157 , $144
a) Mean and sum of deviations
Sum of deviations =
-30 + 55 - 13 - 6 - 65 + 36 + 23 = 0
The sum of deviations is zero dollars.
b) range, variance, and standard deviation
where are data points,
is the mean and n is the number of observations.
Sum of square of differences =
900 + 3025 + 169 + 36 + 4225 + 1296 + 529 = 10180
Sorted data: 56, 91, 108, 115, 144, 157, 176
Range = Maximum - Minimum
Range = 176 - 56 = 120