Chapter 3 - Averages and Variation

55

Find the mean of the data set: 82, 94, 24, 36, 82, 33, 33, 85, 36, 45

65

Find the mode of the data set: 99, 82, 58, 46, 72, 65, 17, 86, 42, 65

14

Find the range of the data set: 6, 20, 11, 19, 9, 19, 9, 8, 17, 18, 7

98

Find the range of the data set: 82, 27, 16, 22, 102, 97, 114, 84, 42, 25, 68, 39

87.8

Find the range of the following data set: 53.18, 71.12, 115.10, 27.30, 36.19, and 66.48

6.19

Find the standard deviation of the data set: 54, 48, 51, 37, 55, 42, 54, 52, 53

10

Find the mean of the data set: 13, 13, 7, 8, 16, 9, 6, 8

Coefficient of Variation

Expresses the standard deviation as a percentage of the sample mean.

19.3

Find a 5% trimmed mean of the following data set: 3, 5, 6, 6, 9, 10, 12, 15, 16, 19, 19, 20, 22, 28, 29, 31, 32, 32, 36, 40

6

Find quartile 1 for the following data set: 8, 7, 6, 9, 9, 5, 3, 8, 10, 9, 8, 8, 6, 5, 6, 7, 8, 9, 1, 9, 7, 8, 6, 2

42.5

Find quartile 2 of the following data set: 11, 54, 27, 31, 69, 15, 57, 63, 31, 72

7

Find the interquartile range of the following data set: 1, 3, 8, 4, 10, 11, 15, 2, 12, 6, 7, 8, 9, 18, 19, 5

12

Find the median of the data set: 17, 8, 8, 15, 16, 15, 10, 10, 6, 15, 12

46.5

Find the median of the data set: 43, 61, 79, 27, 71, 18, 30, 41, 55, 50, 13, 88

8.79

Find the standard deviation of the following data set: 22, 5, 28, 18, 27, 24, 20, 14, 4

38.28

Find the variance of the data set: 54, 48, 51, 37, 55, 42, 54, 52, 53

3.47

If the coefficient of variation is 5.78%, and the sample mean is 60, what is the standard deviation?

54%

If your ACT score was at the 46th percentile, how many other students scored at or above you?

90.1%

Let's say that in your college Math course, Homework is worth 30% of your grade, Tests are worth 50%, and Quizzes are worth 20%. At the end of the first semester, you had a 93% average on homework, 88% average on tests, and a 91% average on quizzes. What is your WEIGHTED AVERAGE in the course?

65%

Roger scored at the 65th percentile on the SAT. How many students scored at or below Roger?

Range

The difference between the largest and smallest values of a data distribution.

Variance

The average of the squared difference from the mean.

Median

The central value of an ordered distribution.

Standard Deviation

The square root of the average of the squared difference from the mean.

Mode

The value in a data set that occurs more frequently.

Percentile

This is a value such that P% of the data fall at or below it and (100-P)% of the data fall at or above it.

Mean

We find this by adding the values of all the entries and then dividing by the number of entries.

19

What is quartile 1 of the RIGHT box-and-whisker plot?

20

What is quartile 3 of the LEFT box-and-whisker plot?

3.1%

What is the coefficient of variation of a data set that has a standard deviation of 1.92 and a mean of 62.51?

30

What is the highest value of the RIGHT box-and-whisker plot?

22.5

What is the median of the RIGHT box-and-whisker plot?