Organizing data
Answers are for parents and teachers.
1
Make a frequency table for 2, 3, 2, 4, 3, 2, 5, 3, 2, 4 and give the mode.
2 occurs 4 times, 3 occurs 3, 4 occurs 2, 5 occurs 1 (total 10). The mode is 2.
2
Data: 14, 22, 9, 31, 27, 18, 12, 25. Find the range and make a frequency table with intervals of 10 starting at 0.
Range = 31 − 9 = 22. 0 to under 10: 1. 10 to under 20: 3. 20 to under 30: 3. 30 to under 40: 1. Total 8.
3
Make a stem-and-leaf plot for 45, 52, 47, 58, 51, 45 with a key.
Sorted: 45, 45, 47, 51, 52, 58. Stem 4: leaves 5 5 7. Stem 5: leaves 1 2 8. Key: 4 | 5 means 45.
4
Find the minimum, Q1, median, Q3 and maximum of 2, 5, 7, 9, 12, 14, 20.
Minimum 2, Q1 = 5, median 9, Q3 = 14, maximum 20.
5
A graph shows 60 and 63 with an axis that starts at 58. The second bar is 5 units tall and the first is 2. Why is this misleading?
The second bar looks 2.5 times as tall, but 63 is only 1.05 times 60 (5% more).