Question

The median of the following data is 525. Find the missing frequency, if it is given that there are 100 observation in the data:

Class interval	Frequency	Class interval	Frequency
0−100 100−200 200−300 300−400 400−500	2 5 f1 12 17	500−600 600−700 700−800 800−900 900−1000	20 f2 9 7 4

Answer 1

Given: Median = 525

We prepare the cumulative frequency table, as given below.

Now, we have

.....(1)

So,

Since median = 525 so the median class is .

Here,

We know that

Putting the value of in (1), we get

Hence, the missing frequencies are 9 and 15.