Finding Mode for Grouped Frequency Distribution with Unequal Class Length

[Suvadip]

How to find mode for grouped frequency distribution with unequal class length? I have to find the mode for the following problem:

Marks No of students

0-20 32
20-50 45
50-70 15
70-100 8For equal class length, we use the formula

\(\displaystyle Mode= l+\frac{f_0-f_{-1}}{2f_0-f_{-1}-f_{+1}}\)

But how to proceed for the above example?

 

[Valkarie]

In this case, you would need to calculate the median marks for each class interval, and then compare the medians to determine which interval has the largest number of students. The interval with the highest median will have the mode. For example, if we calculate the median marks for each interval, it would be:0-20: 1020-50: 3550-70: 6070-100: 85The interval with the highest median is 20-50, so the mode is 20-50.