Measures of Central Tendency and Measures of Dispersion

Probability & StatisticsSections 2.3, 2.4

A. The mean is very low.B. The data values are all very close in value.C. The data values must all be the same.D. All the data values must be 0.

What does a standard deviation of 0 mean?

Stem-and-Leaf Plot Find the range of the stem-and-leaf plot

5 1 2

6 0 4 6 7 7

7 0 2 2 9

8 1 4 6 6 6 9

9

10 8 8 8 9

11 4 5

Key 5|1=5.1

6.4

A. 3B. 3 or -3C. -3D. 81

If the sample variance is calculated and found to be s2 = 9, what is the standard deviation?

If the sample variance is calculated and found to be s2 = 9, what is the standard deviation?

A. 61.5B. 7.8C. 246D. 7.0

Given the extension table below, find the sample standard deviation using the formula {image} for the sample variance. x {image} {image} 24 -10 100 37 3 9 34 0 0 45 11 121 30 -4 16

Given the extension table below, find the sample standard deviation using the formula for the sample variance.

2( )

1

x x

n

( )x x 2( )x xx

24 -10 100

37 3 9

34 0 0

45 11 121

30 -4 16

A. age of college students at local community college

B. heights of college students

C. grades on a very difficult statistics exam

D. age at which death occurs

Which variable would most likely have a left-skewed distribution?

A. 3, 3, 3, 3, 3B. 0, 3, 3, 3, 6C. 1, 4, 2, 2, 6D. 3, 3, 3, 3, 5

Which of the following data sets does not have a mean of 3?

A. 2B. 6C. 8D. 7

What is the median of the data set {4, 7, 8, 2, 9}?

A. 46B. 50C. 48D. 38

Find the median age of the math department if the members' ages are: 30, 46, 50, 26, 70, 57

A. 60B. 65C. 70D. 75E. 85

The histogram of 19 exam scores is given below. Estimate the median score. {image}

The histogram of 19 exam scores is given below. Estimate the median score.

A. 2, 3, 4, 2, 6B. 1, 6, 5, 4, 1C. 7, 1, 1, 2, 6D. 2, 2, 1, 1, 4

Which set of numbers has a mean that is equal to its median?

A. 7, 7, 7, 5, 2B. 1, 1, 3, 4, 5C. 8, 3, 7, 3, 2D. 5, 5, 5, 1, 1

Which data set has the mode of 3?

A. midrangeB. medianC. meanD. mode

Consider the data set {11, 14, 6, 11, 3}. After a typographical error is discovered, the first 11 was changed to a 17. Which of the following would remain unchanged?

A. uniformB. symmetricC. right-skewedD. left-skewed

What word best describes a distribution whose mean is significantly larger than its median?

A. 6B. 21C. 23D. 10.5

Consider the weights (in pounds) of the five children at a local daycare center:24, 37, 34, 45, 30What is the range?