Question

The following is the frequency distribution for the speeds of a sample of automobiles traveling on...

The following is the frequency distribution for the speeds of a sample of automobiles traveling on an interstate highway.

Speed (mph)

Frequency

50−54

  2

55−59

  4

60−64

  5

65−69

10

70−74

  9

75−79

  5

35

The mean is 67

How to find the Variance?

Homework Answers

Answer #1

Ans.

Speed(mph) frequency(fi) midpoint (xi)
50-54 2 52 225 450
55-59 4 57 100 400
60-64 5 62 25 125
65-69 10 67 0 0
70-74 9 72 25 225
75-79 5 77 100 500
Sum = 35 1700

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