Plzz answer ques 53 10
15
20
20
{Mean = 12 4: Standard devta'i00 5 C V 47
53. The following table shows the marks obtained by 60 students, Calculate mean and standard deviation.
Marks (more than)
No. of students
Hint: First, convert the given series as ordinary continuous series and then use the step deviation method,
(Mean 51 67 marks: Standard deviat'on=: 1513
54. Calculate standard deviation and coefficient of dispersion from the data below:
Mid-Points
15
10
10
Hint: For coefficient of dispersion, calculate coefficient of variation as it is a better measure in corrpæso
to coefficient of standard deaaux
{Standard 18.49. C V z '1
