The lowest overnight temperatures, in °C, on seven nights were 4, −3, 7, 0, −1, 5 and 2. What is the range?
Edexcel 2c.01, Edexcel 2c.04 · Averages and spread
Range, quartiles, interquartile range and percentiles
Foundation and Higher questions. Foundation · Higher · The lesson
Eleven students' test marks, in order, are 12, 15, 18, 18, 21, 23, 26, 27, 30, 34, 41. What is the interquartile range?
Commute times
A company asked 80 staff how long, in minutes, they take to travel to work. The table shows the results.
| Time (t minutes) | Frequency |
|---|---|
| 0 < t ≤ 10 | 4 |
| 10 < t ≤ 20 | 16 |
| 20 < t ≤ 30 | 28 |
| 30 < t ≤ 50 | 20 |
| 50 < t ≤ 80 | 12 |
Estimate the 10th percentile of the commute times.
Estimate the 90th percentile of the commute times.
Work out an estimate of the interdecile range.
Give one reason the interdecile range can suit these data better than the range.
The box plots show two classes' marks out of 80 in the same test. Which statement compares the spread correctly?
A gardener measured seven sunflower seedlings, in cm: 23, 8, 15, 31, 12, 19, 27. Work out the interquartile range.
A list of 19 values is in order from smallest to largest. Which value is the upper quartile?