These Statistics Class 11 Maths Extra Questions and Answers are most important for your upcoming examinations including JEE Main & JEE Advanced. These Statistics Class 11 Maths Extra Questions and Answers will help you to score good marks in your exams by helping you to prepare the concepts better and hence, help you to understand the concepts more clearly.

## Statistics Class 11 Maths Extra Questions and Answers

1. If the mean of the following data is 20.6, then the value of p is

x: 10 15 p 25 35

: 3 10 25 7 5

(A) 30

(B) 20

(C) 25

(D) 10

**Answer:** 20

2. In a symmetric distribution

(A) Mean ≠ Median = Mode

(B) Mean = Median ≠ Mode

(C) Mean ≠ Median ≠ Mode

(D) Mean = Median = Mode

**Answer:** Mean = Median = Mode

3. The algebraic sum of the deviation of 20 observations measured from 30 is 2. So, the mean of observations is

(A) 30.0

(B) 30.1

(C) 30.2

(D) 30.3

**Answer:** 30.1

4. If x and y are independent variables, the Cov(x, y) equals

(A) 1

(B) -1

(C) 0

(D) None of these

**Answer:** 0

5. If one of the observation is zero then geometric mean is

(A) (Sum of observation)/n

(B) (Multiplication of all observations)n

(C) (Multiplication of all observations)1/n

(D) 0

**Answer:** 0

6. Varience of the following data 2, 4, 5, 6, 8, 17 is

(A) 13.33

(B) 23.33

(C) 33.33

(D) None of these

**Answer:** 23.33

7. The mean and variance of 7 observations are 8 and 16, respectively. If five of the observations are 2, 4, 10, 12, 14. then the remaining two observations are

(A) 4, 6

(B) 6, 8

(C) 8, 10

(D) 10, 12

**Answer:** 6, 8

8. If one of the observation is zero then geometric mean is

(A) (Sum of observation)/n

(B) (Multiplication of all observations)n

(C) (Multiplication of all observations)1/n

(D) 0

**Answer:** 0

9. If the varience of the data is 121 then the standard deviation of the data is

(A) 121

(B) 11

(C) 12

(D) 21

**Answer:** 11

10. The median and SD of a distributed are 20 and 4 respectively. If each item is increased by 2, the new median and SD are

(A) 20, 4

(B) 22, 6

(C) 22, 4

(D) 20, 6

**Answer:** 22, 4

11. The mean of a group of 100 observations was found to be 20. Later on, it was found that three observations were incorrect, which was recorded as 21, 21 and 18. Then the mean if the incorrect observations are omitted is

(A) 18

(B) 20

(C) 22

(D) 24

**Answer:** 20

12. If the mean of first n natural numbers is 5n/9, then n =

(A) 5

(B) 4

(C) 9

(D) 10

**Answer:** 9

13. If r is the correlation coefficient, then

(A) |r| ≤ 1

(B) r ≤ 1

(C) |r| ≥ 1

(D) r ≥ 1

**Answer:** |r| ≤ 1

14. If a variable takes discrete values x + 4, x – 7/2, x – 5/2, x – 3, x – 2, x + 1/2, x – 1/2, x + 5 (x > 0), then the median is

(A) x – 5/4

(B) x – 1/2

(C) x – 2

(D) x + 5/4

**Answer:** x – 5/4

15. Range of the data 4, 7, 8, 9, 10, 12, 13 and 17 is

(A) 4

(B) 17

(C) 13

(D) 21

**Answer:** 13

16. When tested the lives (in hours) of 5 bulbs were noted as follows: 1357, 1090, 1666, 1494, 1623. The mean of the lives of 5 bulbs is

(A) 1445

(B) 1446

(C) 1447

(D) 1448

**Answer:** 1446

17. Which one is measure of dispersion method

(A) Renge

(B) Quartile deviation

(C) Mean deviation

(D) all of the above

**Answer:** all of the above

18. The coefficient of variation is computed by

(A) S.D/.Mean×100

(B) S.D./Mean

(C) Mean./S.D×100

(D) Mean/S.D.

**Answer:** S.D./Mean

19. If the difference of mode and median of a data is 24, then the difference of median and mean is

(A) 12

(B) 24

(C) 8

(D) 36

**Answer:** 12

20. If covariance between two variables is 0, then the correlation coefficient between them is

(A) nothing can be said

(B) 0

(C) positive

(D) negative

**Answer:** 0