Consider the following frequency distribution for the next three (03) items follow :

Class	0-20	20-40	40-60	60-80	80-100
Frequency	17	p + q	32	p - 3q	19

 

The total frequency is 120. The mean is 50.

If the frequency of each class is doubled, then what would be the mean?

If M is the mean of n observations x₁ - k, x₂ - k, x₃ - k, _ _ _, x_n - k, where k is any real number, then what is the mean of x₁, x₂, x₃, _ _ _, x_n?

What is the sum of deviations of the variate values 73, 85, 92, 105, 120 from their mean?

If the mean of a frequency distribution is 100 and the coefficient of variation is 45%, then what is the value of the variance?