Testing Here is an ordered list of midterm test scores for a Spanish class. What value is at the 65th percentile?
41 | 54 | 61 | 65 | 67 | 73 | 74 |
77 | 77 | 77 | 79 | 80 | 82 | 88 |
89 | 93 | 97 | 98 | 98 | 100 |
What should you do first to find percentiles?
Put the data in order.
Of the 20 values, 65% fall at or below the value at the 65th percentile.
13 values fall at or below 82, the value at the 65th percentile.
Identify the outlier in the data set. Then find the mean, median, and mode of the data set when the outlier is included and when it is not.
Find the values at the 40th and 80th percentiles for the values below.
58 53 35 60 58 42 57 60 43 44 51 49 58
Vocabulary Which measure of central tendency would best represent the values below? Explain your reasoning.
4 1 5 5 6 8 9 5 5 3 2 7 5 5 1
Error Analysis A student found the median of the data set below. Explain the student's error. What is the median?
Score | 80 | 85 | 90 | 95 |
---|---|---|---|---|
Frequency | 6 | 4 | 10 | 1 |
A Practice
See Problem 1.
Find the mean, median, and mode of each set of values.
Age (years) | 13 | 14 | 15 | 16 | 17 | 18 | 19 |
---|---|---|---|---|---|---|---|
Frequency | 7 | 12 | 18 | 9 | 5 | 4 | 2 |