Calculate the median class for the following data

Explanation

From the given table , we may get back frequencies and cumulative frequencies as shown below

Now , `N=7o rArr N/2=35 `
The cumulative freqeuency just greater than 35 is 41 and the corresponding class is 30-40
Thus the median class is 30-40
`therefore l=30 , h=10, f=12, cf=c.f " of preceding class " =29 and N/2=35`
Median , `M_e=l+{hxx((N/2-cf))/f} =30+{((35-29))/(12)}=35` Hence , the required median is 35