CBSE - Statistics

1 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

2 Statistics 

The median of first 12 prime numbers is : 

(1) 13  
(2) 14 
(3) 15 
(4) 17

3 Statistics 

The highest score of a certain data exceeds in lowest score by 16 and coefficient of range is 1/3. The sum of the highest score and the lowest score is

(1) 36
(2) 48
(3) 24
(4) 18

4 Statistics 

The mean yearly salary of an employee of acompany was Rs. 20,000. If the mean yearly salaries of male and female employees were Rs. 20800 and Rs. 16800  respectively, then the percentages of males and females employed in the company respectively are

(1) 80% and 20%
(2) 70% and 30%
(3) 55% and 45%
(4) 50% and 50%

5 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

6 Statistics 

The arithmetic mean and mode of a data are 24 and 12 respectively, Then the median of the data is 

(1) 20
(2) 18
(3) 21
(4) 22

7 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 

8 Statistics 

The mean and median of the data x,y,z are 50 and 35respectively, where x<y<z. If z−x=55, then the value of (y−x) is

(1) 8
(2) 7
(3) 3
(4) 5

9 Statistics 

The median from the following distribution is 

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

10 Statistics 

Compute mode for the following data

7, 7, 8, 8, 8, 9, 9, 10, 10, 10, 11, 11, 12, 13, 13

1) 10.4
2) 10.2
3) 9.8
4) 10.5