Mathematics
Mathematics
Problem
The marks (out of 50) obtained by 40 students are grouped as follows: Class (marks) 0–10 10–20 20–30 30–40 40–50 Frequency 5 9 12 8 6 What is the cumulative frequency for “less than 40” marks? a) b) c) d)Intuitive explanation
Cumulative frequency tracks how many data points fall up to and including each class boundary—it's a running total as you move through the groups. To find "less than 40," you simply add up all the frequencies for classes that end before 40: that's 0–10, 10–20, 20–30, and 30–40. This builds your intuition for how cumulative frequency helps you answer "how many students scored below a certain threshold?"
Intuitive explanation
Cumulative frequency tracks how many data points fall up to and including each class boundary—it's a running total as you move through the groups. To find "less than 40," you simply add up all the frequencies for classes that end before 40: that's 0–10, 10–20, 20–30, and 30–40. This builds your intuition for how cumulative frequency helps you answer "how many students scored below a certain threshold?"