LESSON Practice A 11-5 Measures of Central Tendency and Variation

Name

Date

Class

LESSON Practice A 11-5 Measures of Central Tendency and Variation

Find the mean, median, and mode of each data set.

1. {3, 10, 2, 8, 7, 5, 2, 5}

a. The mean is the sum of the values in a set divided by the number of values. Find the mean of the set.

5.25

b. The median is the middle value when the set is

ordered numerically. Find the median of the set.

5

c. The mode is the value or values that occur most often. Find the mode of the set.

2, 5

2. {11, 15, 4, 10, 7, 5, 11, 9}

a. Mean

b. Median

c. Mode

9

9.5

11

Find the expected values.

3. The probability distribution for the number of free throws that Larry makes in a game is given below. Find the expected number of free throws that Larry makes in a game.

Number of Free Throws Made, n 5

6

7

Probability

0.21 0.58 0.14

4. The probability distribution for the number of pieces of junk mail May receives is given below. Find the expected number of junk mail letters May receives in a day.

Number of Junk Mail Letters, n 1

2

3

Probability

0.15 0.70 0.10

6.07

8 0.07

2.05

4 0.05

Make a box-and-whisker plot of the data. Find the interquartile range.

5. {3, 7, 5, 3, 5, 9, 2, 7}

Interquartile range is 4.

6. {1, 9, 9, 2, 2, 5, 5, 10}

Interquartile range is 7.

Find the variance and standard deviation. 7. {1, 2, 8, 11, 7, 10, 7, 2}

13; 3.6

8. {10, 14, 8, 12, 9, 13}

4.7; 2.2

Copyright ? by Holt, Rinehart and Winston. All rights reserved.

35

Holt Algebra 2

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Copyright ? by Holt, Rinehart and Winston. All rights reserved.

59

Holt Algebra 2

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