Find the median of the following data:

Here, the class mark is given.

∴Class size = 45 – 35 = 10

If a is a class mark and h is the size of the class interval, then the lower limit and upper limit of the class interval are and repectively.

∴, we have h = 10

∴Lower Limit of first class interval

The upper limit of first class interval

∴ The first class interval is 30 – 40

Hence, the class intervals are 30 – 40, 40 – 50, 50 – 60, 60 – 70, 70 – 80, 80 – 90.

Now, We find the median

We have n = 90

So,

The cumulative Frequency just greater than is 46 then the median class is 40 – 50 such that

the lower limit (l) = 40

cumulative frequency of the class preceding 40 – 50 (cf) = 20

frequency of the median class 40 – 50 = 26,

class size (h) = 10

Using the formula,, we have

= 40 + 9.61

= 49.61