these two qus plsss 12. Calculate the standard deviation of marks secured by 100 examinees in the
examination.
Marks
No. of
exammees
10-20
20-30
30-40
50-60
24
60-70
2
70-80
19
3
2
40-50
49
80-90
13. Find out standard deviation and its coefficient of the following series.
Size
10
Fr uency 6
20
8
30
16
40
15
50
33
60
11
70
12
14. The sum of 10 values is 100 and the sum of their squares is 1090. Find the coefficient
of variation.
15. Calculate the coefficient of variation from the following data:
Variables
Fr uencies
10
6
20
8
30
16
40
15
50
32
60
11
70
12