Handling Data 2
2 marks · EasyThe heights, in metres, of a random sample of 12 plants are grouped as shown.
| Height (h, m) | Frequency |
|---|---|
| 0.5 ≤ h < 1.0 | 2 |
| 1.0 ≤ h < 1.5 | 6 |
| 1.5 ≤ h < 2.0 | 4 |
Write down the modal class.
What is the group containing the median height?
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) 1.0 ≤ h < 1.5
(b) 1.0 ≤ h < 1.5
Also accept: 1.0 ≤ h < 1.5 for both parts if justified
Common mistakes: Confusing modal with median class
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Correct modal class: 1.0 ≤ h < 1.5 (highest frequency).
B1 (b) · 1 mark · Correct median class: 1.0 ≤ h < 1.5 (contains the 6th and 7th values).
Worked solution
a) The modal class is the group with the highest frequency: 6 for 1.0 ≤ h < 1.5.
b) The median lies in the group containing the 6th and 7th values (since total frequency = 12).
Cumulative frequency: 2 (first group), 8 (second), 12 (third).
So, values 3–8 are in 1.0 ≤ h < 1.5. Median class is 1.0 ≤ h < 1.5.