The table shows the distribution of marks obtained by some students in a test
| Marks | 0-9 | 10-19 | 20-29 | 30-39 | 40-49 |
| Frequency | 4 | 12 | 16 | 6 | 2 |
What is the upper class boundary of the upper quartile class?
49.5
39.5
29.5
19.5
Correct answer is C
£f = 4 + 12 + 16 + 6 +2 = 40
Upper quartile class
= 3/4 of 40 = 30th position
Counting from the distribution table to the 30th position,
the upper class boundary is 29.5