Question
Mr. Jacobs is going to make a histogram of the test scores from the last math test he gave. He plans to first organize the data into a stem-and-leaf plot and then make the histogram from the stem-and-leaf plot. The test scores are listed below. 79, 82, 65, 61, 94, 97, 84, 77, 89, 91, 90, 83, 99, 71, 68, 77, 87, 85 Which of the following expressions could be used to find how many students scored less than a 90 on the test? 3 + 4 + 6 + 1 4 + 6 3 + 4 + 6 3 + 4
Answer
3 + 4 + 3 = 10
- Understand the problem. A histogram of test scores from the last math test is being created. First, the data will be organized into a stem-and-leaf plot. We want to find out how many students scored less than 90 on the test.
- Create the stem-and-leaf plot. 6 | 5 8 7 | 1 7 7 9 8 | 3 4 4 5 7 9 9 | 0 1 4 7 9 9
- Count the number of students who scored less than 90. There are 10 students who scored less than 90: 6 students scored less than 70, 2 students scored 70-79, and 2 students scored 80-89. 3 + 4 + 3 = 10.