Answer:
(A) what is the average number of units sold for 50 days: 820, 1830, 1040, 850, 6
(B) what is the standard deviation
(C) what is the average number of units sold for 5 days: 86, 23, 73, 40, 95
(D) can we conclude that the sales are random?
Explanation:
(A)
(820×10) + (1830×10) + (1040×10) + (850×10) + (6×10) = 45,460
45,460÷50 = 909.2units
(B)
(909.2-820)^2 × 10 = total squared mean deviation of the first 10 sales or 10days - sales of 820 per day
Doing same for the other 4 values, the total of squared mean deviation for the 5 days is
16922128÷50 = 338442.56 = Variance of the set of sales values
Standard Deviation is the square root of Variance so it is 581.758
(C) Mean of random units sold in 5 days: 317÷5 = 63.4
(D) for 50 days, mean sale was 909.2 units
For 5 days, random mean sale was 63.4
50÷5=10
909.2÷63.4=14.34
Yes, we can conclude that the sales are random
