CBSE - Statistics

1 Statistics 

The mean age of a combined group of men and women is 25 years. If the mean age of the group of men is 26 and that of the group of women is 21, then the percentage of men and women in the group is

(1) 60, 40
(2) 80, 20
(3) 20, 80
(4) 40, 60

2 Statistics 

A family spends Rs. 6,000 p.m. to meet the monthly expenditure. The expenditure has been shown in the given pie diagram. The miscellaneous expenditure is

(1) Rs. 1,500
(2) Rs. 2,000 
(3) Rs. 1,200
(4) Rs. 3,000

3 Statistics 

If the median of the data x1,x2,x3,x4,x5,x6,x7,x8 is α and x1<x2<x3<x4<x5<x6<x7<x8, then the median of x3,x4,x5,x6 is

(1) α
(2) α / 2
(3) α / 3
(4) α / 4

4 Statistics 

When 10  is subtracted from all the observations, the mean is reduced to 60%  of its value. If 5 is added to all the observations, then the mean will be

(1) 25
(2) 30 
(3) 60
(4) 65 

5 Statistics 

Find the median of the following values :
37, 31, 42, 43, 46, 25, 39, 45, 32

1) 31
2) 46
3) 39
4)  43

6 Statistics 

The frequency distribution of marks obtained by 28 students in a test carrying 40 marks is given below

If the mean of the above data is 20, then the difference between x and y is 
(1) 3
(2) 2
(3) 1
(4) 0

7 Statistics 

If the mean of the lower and upper quartile is 10 and semi-interquartile range is 5, then the lower quartile and upper quartile respectively are

(1) 2 and 12
(2) 3 and 13
(3) 4 and 14
(4) 5 and 15

8 Statistics 

The median from the following distribution is 

(1) 19
(2) 19.5
(3) 20
(4) 18

9 Statistics 

A school has 20 teachers, one of them retires at the age of 60  years and a new teacher replaces him, this  change reduces the average  age of the staff by 2 years,  the age of new teacher is 

(1) 28 years
(2) 25 years
(3) 20 years
(4) 18 years

10 Statistics 

If number 6, 8, 2x – 5, 2x – 1, 15, 17, 20 and 22 are in asending order and its mediun is 14 t hen the value of x will be

(1) 14 
(2) 7 
(3) 15 
(4) 20