SOLUTION: The following is the frequency distribution for the speeds of a sample of automobiles traveling on an interstate highway. Speed Miles per Hour Frequency 50

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Question 869872: The following is the frequency distribution for the speeds of a sample of automobiles traveling on an interstate highway.
Speed
Miles per Hour Frequency
50 - 54 2
55 - 59 4
60 - 64 5
65 - 69 10
70 - 74 9
75 - 79 5
35
31. Refer to Exhibit 3-4. The mean is
a. 35
b. 670
c. 10
d. 67
e. None of the above answers is correct.
ANSWER:
32. Refer to Exhibit 3-4. The variance is
a. 6.969
b. 7.071
c. 48.570
d. 50.000
e. None of the above answers is correct.
ANSWER:
33. Refer to Exhibit 3-4. The standard deviation is
a. 6.969
b. 7.071
c. 48.570
d. 50.000
e. None of the above answers is correct.
ANSWER:

Found 2 solutions by ewatrrr, Fombitz:
Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!

Hi
x n x -67 n(x-67)^2
52 2 104 -15 450
57 4 228 -10 400
62 5 310 -5 125
67 10 670 0 0
72 9 648 5 225
77 5 385 10 500
35 2345 -15 1700
mean 67 50 Variance (n-1) Used
7.071067812 SD
If Assignment calls for 35 rather than 34 to be used to determine Variance, answers would be:
Variance = 48.57143 and 6.969

Answer by Fombitz(32388) (Show Source):
You can put this solution on YOUR website!

SOLUTION: The following is the frequency distribution for the speeds of a sample of automobiles traveling on an interstate highway. Speed Miles per Hour Frequency 50 - 54 2 55 -