12. Calculate the mean deviation about median age for the age distribution of 100 persons given below:
Age <br> (in years)
16−20
21−25
26−30
31−35
36−40
41−45
46−50
51−55
Number
5
6
12
14
26
12
16
9
[Hint Convert the given data into continuous frequency distribution by subtracting 0.5 from the lower limit and adding 0.5 to the upper limit of each class interval]