A sample of 5 months of sales data provided the following information: Month 1 2 3 4 5
Units Sold 97 120 88 97 93

Required:
a. Develop a point estimate of the population mean number of units sold per month (to 1 decimal).
b. Develop a point estimate of the population standard deviation (to 2 decimals).

a. 99

b. 12.31

Step-by-step explanation:

a. Estimate of the population mean number of units sold per month

n = Number of Data Values = 5

Sum of Data Values = Σxi =97 + 120 + 88 + 97 + 93 =  495

Sample Mean = X = Σxi/n = 495 / 5 = 99

The population mean number of units sold per month is 99

b. Estimate of the population standard deviation

Month    Data (x)     X    x - X    (x - X)^2

   1             97          99     -2         4

   2            120        99      21       441

   3             88         99      -11       121

   4             97         99      -2        4

   5             93         99      6         36

Sum of deviation squared          606

s^2 = Sample Variance = Σ(xi - X)2/(n - 1)

Sample Variance = 606/4 = 151.5

Sample Standard Deviation = √Sample Variance

Sample Standard Deviation = √151.5

Sample Standard Deviation = 12.30853362509117

Sample Standard Deviation = 12.31

The point estimate of the population standard deviation is 12.31

answer: all the values are within because it has a pattern that repeats from -6 to 4.

good luck!