Summarizing Data

Sleep time of 15 students, from least to most. What is the range? From 7 to 10, three hours. What is the mean? About 8.6 hours. What is the median? 8.5 hours. What is the mode?

8, 8.5 and 9, each three times. Phone time of 12 students, from least to most. What is the minimum? 30 minutes. What is the maximum? 150 minutes. What is the range? 150 minus 30, 120 minutes.

What is the mean? 75 minutes. What is the median? 67.5 minutes. Set A. Fourteen values. Look at the shape of Set A. High in the middle, low at the ends. Roughly symmetric. Set B. Eleven values.

Look at the shape of Set B. High on the right, tail points left. Skewed left. Set C. Sixteen values. Look at the shape of Set C. High on the left, tail points right. Skewed right.

Breakfast habits of 200 students. The bottom shows each habit. A bar chart of how often students eat breakfast. What do most students do for breakfast?

Most eat breakfast every day. Eighty-five students. What is the shape of the distribution? It falls from every day to never. What can the school do to improve?

Encourage the students who sometimes or never eat breakfast. Class 3. Twelve students took the test. What is the mean of Class 3? About 80.2. What is the range of Class 3? 95 minus 65, 30.

Class 4. Twelve students took the test. What is the mean of Class 4? About 77.9. What is the range of Class 4? 100 minus 50, 50. Class 3 has a smaller range, so Class 3 is more consistent.

Weekly exercise time of 10 students, from least to most. What is the range? 300 minus 90, 210 minutes. What is the mean? 165 minutes. What is the median? 150 minutes. What is the mode?

150, three students. The value 300 is much higher than the others. It is an outlier. Most students exercise about 150 minutes a week. One student exercises much more.