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# Standard Deviation Calculations

Find the standard deviation for the given data. Round your answer to one more decimal place than the original data.
54)

15, 42, 53, 7, 9, 12, 14, 28, 47

54)

______
A)

15.8

B)

29.1

C)

17.8

D)

16.6

Use the empirical rule to solve the problem.
55)

The systolic blood pressure of 18-year-old women is normally distributed with a mean of 120 mmHg and a standard deviation of 12 mmHg. What percentage of 18-year-old women have a systolic blood pressure between 96 mmHg and 144 mmHg?

55)

______
A)

99.99%

B)

95%

C)

68%

D)

99.7%

Solve the problem.
56)

The heights of the adults in one town have a mean of 67.5 inches and a standard deviation of 3.4 inches. What can you conclude from Chebyshev's theorem about the percentage of adults in the town whose heights are between 60.7 and 74.3 inches?

56)

______
A)

The percentage is at most 75%

B)

The percentage is at most 95%
C)

The percentage is at least 75%

D)

The percentage is at least 95%

Solve the problem. Round results to the nearest hundredth.
57)

Scores on a test have a mean of 71 and a standard deviation of 9. Michelle has a score of 89. Convert Michelle's score to a z-score.

57)

______
A)

2

B)

-18

C)

18

D)

-2

Find the z-score corresponding to the given value and use the z-score to determine whether the value is unusual. Consider a score to be unusual if its z-score is less than -2.00 or greater than 2.00. Round the z-score to the nearest tenth if necessary.
58)

A test score of 54.0 on a test having a mean of 73 and a standard deviation of 10.

58)

______
A)

-1.9; not unusual

B)

-19; unusual
C)

1.9; not unusual

D)

-1.9; unusual

Determine which score corresponds to the higher relative position.
59)

Which is better, a score of 92 on a test with a mean of 71 and a standard deviation of 15, or a score of 688 on a test with a mean of 493 and a standard deviation of 150?

59)

______
A)

A score of 688
B)

Both scores have the same relative position.
C)

A score of 92

Find the percentile for the data point.
60)

Data set: 55 46 30 63 63 65 42;
data point 55

60)

______
A)

43

B)

57

C)

50

D)

20

Find the indicated measure.
61)

Use the given sample data to find .Q2
49 52 52 52 74 67 55 55

61)

______
A)

55.0

B)

61.0

C)

67.0

D)

6.0

#### Solution Preview

Find the standard deviation for the given data. Round your answer to one more decimal place than the original data.
54)

15, 42, 53, 7, 9, 12, 14, 28, 47

______
C) 17.8

Use the empirical rule to solve the problem.
55)

The systolic blood pressure of 18-year-old women is normally distributed with a mean of 120 mmHg and a standard deviation of 12 mmHg. What percentage of 18-year-old women have a systolic blood pressure between 96 mmHg and 144 mmHg?

B)

95%

Solve ...

#### Solution Summary

The solution provides a brief standard deviation calculation

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