Question

This question is all together so all steps must be answered please!

Members of a labor union were asked their ages. The frequency distribution for this sample is given below. Ages, in years

Class limits frequency

15 – 24 60

25 – 34 195

35 – 44 283

45 – 54    140

55 – 64 42

65 - 74    10

[10] (6 pts) Find the mean (show work)

[11] (3 pts) Identify the modal class

[12] (6 pts) Calculate the variance (show work)

[13] (3 pts) Calculate the standard deviation

Answer 1

Solution :

Class limits frequency midpoint
f x

15 – 24 60 19.5

25 – 34 195 29.5

35 – 44 283 39.5

45 – 54 140 49.5

55 – 64 42 59.5

65 - 74 10 69.5

[10] => mean = 38.6640

[11] => Modal class is 35 - 44

The modal class is the group with the highest frequency.in this group 35 - 44 jas the highest frequency that is 283

[12] => variance = 113.5670

[13] => standard deviation = 10.6570