The cumulative frequency of a set of data or class intervals of a frequency table is the sum of the frequencies of the data up to a required level. It can be used to determine the number of items that have values below a particular level.
Example : (Ungrouped data)
The following table gives the frequency distribution of marks obtained by 28 students in a particular test.
Marks
30
31
32
33
Frequency
5
7
10
6
Construct a cumulative frequency table for the given data.
Solution:
Marks
Frequency
Marks less than
Cumulative Frequency
30
5
30
5
31
7
31
5 + 7 =12
32
10
32
12 + 10 =22
33
6
33
22 + 6 =28
Example : (Grouped data)
The following table gives the frequency distribution of mass of 40 objects.
Mass (g)
10–14
15–19
20–24
25–29
30–34
35–39
40–44
Frequency
3
4
10
12
6
3
2
Construct a cumulative frequency table for the given data.
Solution:
Mass
Upper class boundaries
Frequency
Mass less than
Cumulative Frequency
10 – 14
14.5
3
14.5
3
15 – 19
19.5
4
19.5
3 + 4 = 7
20 – 24
24.5
10
24.5
7 + 10 = 17
25 – 29
29.5
12
29.5
17 + 12 = 29
30 – 34
34.5
6
34.5
29 + 6 = 35
35 – 39
39.5
3
39.5
35 + 3 = 38
40 – 44
44.5
2
44.5
38 + 2 = 40
The following video how to construct the cumulative frequency table and cumulative frequency graph.
Custom Search
We welcome your feedback, comments and questions about this site - please submit your feedback via our Feedback page.