NEED ASAP. CHECK COMMENTS FOR ADDITIONAL INSTRUCTIONs

Exhibit 3-4

The following is thefrequency distributionfor 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:

34. Which of the following is not a measure of dispersion?

a. the range

b. the 50th percentile

c. the standard deviation

d. the interquartile range

e. the variance

ANSWER:

35. If the variance of a data set is correctly computed with the formula using n - 1 in the denominator, which of the following is true?

a. the data set is a sample

b. the data set is a population

c. the data set could be either a sample or a population

d. the data set is from a census

e. None of the above answers is correct.

ANSWER:

36. In computingdescriptive statisticsfrom grouped data,

a. data values are treated as if they occur at the midpoint of a class

b. the grouped data result is more accurate than the ungrouped result

c. the grouped data computations are used only when a population is being analyzed

d. All of the above answers are correct.

e. None of the above answers is correct.

ANSWER:

37. The measure of dispersion that is influenced most by extreme values is

a. the variance

b. the standard deviation

c. the range

d. the interquartile range

e. None of the above answers is correct.

ANSWER:

38. When should measures of location and dispersion be computed from grouped data rather than from individual data values?

a. as much as possible since computations are easier

b. only when individual data values are unavailable

c. whenever computer packages for descriptive statistics are unavailable

d. only when the data are from a population

e. None of the above answers is correct.

ANSWER:

39. The descriptive measure of dispersion that is based on the concept of a deviation about the mean is

a. the range

b. the interquartile range

c. both a and b

d. the standard deviation

e. None of the above answers is correct.

ANSWER:

40. For Z =5, state the Chebychev's inequality.

Directions: Answer all Questions and please give me a justification on why you chose that answer. Thank you.