Q1 of 37 Page 14

Find the class marks of classes 10 - 25 and 35 - 55. [CBSE 2008]

Class mark is given by

Class mark of class 10 - 25 =

Class mark of class 35 - 55 =

∴ Class mark of class 10 - 25 is 17.5 and 35 - 55 is 45.

Write the median class of the following distribution: [CBSE 2009]

Class	0 - 10	10 - 20	20 - 30	30 - 40	40 - 50	50 - 60	60 - 70
Frequency	4	4	8	10	12	8	4

What is the lower limit of the modal class of the following frequency distribution?[CBSE 2009]

Age (in years)	0 - 10	10 - 20	20 - 30	30 - 40	40 - 50	50 - 60
60 Number of patients	16	13	6	11	27	18

If the mean of 5 observations x, x + 2, x + 4, x + 6 and x + 8 is 11, find the value of x.[CBSE 2014]

If the mean of 25 observations is 27 and each observation is decreased by 7, what will be the new mean?[CBSE 2014]