Please refer to Assignments Class 11 Mathematics Statistics Chapter 15 with solved questions and answers. We have provided Class 11 Mathematics Assignments for all chapters on our website. These problems and solutions for Chapter 15 Statistics Class 11 Mathematics have been prepared as per the latest syllabus and books issued for the current academic year. Learn these solved important questions to get more marks in your class tests and examinations.

## Statistics Assignments Class 11 Mathematics

**Question. Mean of 20 observations is 15.5 Later it was found that the observation 24 was misread as 42. The corrected mean is:**

(a) 14.2

(b) 14.8

(c) 14.0

(d) 14.6

**Answer**

D

**Question. The mean of 5 observation is 4.4 and their variance is 8.24. If three of the observations are 1, 2 and 6, then difference of the other two observations is**

(a) 5

(b) 4

(c) 6

(d) 9

**Answer**

A

**Question. When tested, the lives (in hours) of 5 bulbs were noted as follows****1357, 1090, 1666, 1494, 1623****The mean deviations (in hours) from their mean is**

(a) 178

(b) 179

(c) 220

(d) 356

**Answer**

A

**Question. If you want to measure the intelligence of a group of students,which one of the following measures will be more suitable?**

(a) Arithmetic mean

(b) Mode

(c) Median

(d) Geometric mean

**Answer**

B

**Question. If mean of the n observations x _{1}, x_{2}, x_{3} …., x_{n} be x¯ , then the mean of n observations 2x_{1} + 3, 2x_{2} + 3, 2x_{3} + 3, …., 2x_{n} + 3 is**

(a) 3x¯ + 2

(b) 2x¯+ 3

(c) x¯ + 3

(d) 2x¯

**Answer**

B

**Question. The measure of variability which is independent of units, is called**

(a) mean deviation

(b) variance

(c) standard deviation

(d) coefficient of variation

**Answer**

D

**Question. The mean of six numbers is 30. If one number is excluded, the mean of the remaining numbers is 29. The excluded number is**

(a) 29

(b) 30

(c) 35

(d) 45

**Answer**

C

**Question. The number which indicates variability of data or observations, is called**

(a) measure of central tendency

(b) mean

(c) median

(d) measure of dispersion

**Answer**

D

**Question. Variance of the data 2, 4, 5, 6, 8, 17 is 23.33. Then, variance of 4, 8, 10, 12, 16, 34 will be**

(a) 23.33

(b) 25.33

(c) 93.32

(d) 98.32

**Answer**

C

**Question. If the mean of four observations is 20 and when a constant c is added to each observation, the mean becomes 22. The value of c is :**

(a) – 2

(b) 2

(c) 4

(d) 6

**Answer**

B

**Question. In a batch of 15 students, if the marks of 10 students who passed are 70, 50, 95, 40, 60, 70, 80, 90, 75, 80 then the median marks of all the 15 students is:**

(a) 40

(b) 50

(c) 60

(d) 70

**Answer**

C

**Question. The S. D of 15 items is 6 and if each item is decreased or increased by 1, then standard deviation will be**

(a) 5

(b) 6

(c) 7

(d) None of these

**Answer**

B

**STATEMENT TYPE QUESTIONS**

**Question. If for a distribution ∑(x −5) = 3 , ∑(x − 5) ^{2} = 43 and the total number of items is 18.**

**Statement-I: Mean of the distribution is 4.1666.**

**Statement-II: Standard deviation of the distribution is 1.54.**

(a) Only Statement I is true

(b) Only Statement II is true

(c) Both statements are true

(d) Both statements are false

**Answer**

B

**Question. Consider the following data**

**I. Mean of the data is 22.65.****II. Mean deviation of the data is 1.25.****III. Mean of the data is 21.65.****IV. Mean deviation of the data is 2.25.**

(a) I and II are true

(b) II and III are true

(c) I and IV are true

(d) III and IV are true

**Answer**

B

**Question. Consider the following data**

**I. Median of the data is 11.****II. Median of the data is 12.****III. Mean deviation about the median is 2.25.****IV. Mean deviation about the median is 1.25.**

(a) I and III are true

(b) I and IV are true

(c) II and III are true

(d) II and IV are true

**Answer**

D

**Question. Consider the following frequency distribution**

**I. Mean of the data is 27.****II. Mean of the data is 32.****III. Variance of the data is 132****IV. Variance of the data is 164**

(a) II and IV are true

(b) I and IV are true

(c) II and III are true

(d) I and III are true

**Answer**

D

**Question. Consider the following data****6, 8, 10, 12, 14, 16, 18, 20, 22, 24****I. The variance of the data is 33.****II. The standard deviation of the data is 4.74.**

(a) Only Statement I is true

(b) Only Statement II is true

(c) Both statements are true

(d) Both statements are false

**Answer**

A

**Question. Statement I : The mean deviation about the mean for the data 4, 7, 8, 9, 10, 12, 13, 17 is 3.5.****Statement II : The mean deviation about the mean for the data 38, 70, 48, 40, 42, 55, 63, 46, 54, 44 is 8.5.**

(a) Only Statement I is true

(b) Only Statement II is true

(c) Both statements are true

(d) Both statements are false

**Answer**

D

**Question. Following are the marks obtained, out of 100 by two students Raju and Sita in 10 tests.**

**I. Raju is more intelligent.****II. Sita is more intelligent.****III. Raju is more consistent.****IV. Sita is more consistent.**

(a) I and IV are true

(b) II and III are true

(c) I and III are true

(d) II and IV are true

**Answer**

B

**Question. Statement-I : The mean and variance for first n natural numbers are n + 1/2 and n ^{2} + 1/12, respectively.**

**Statement-II : The mean and variance for first 10 positive multiples of 3 are 16.5 and 74.25. respectively.**

(a) Only Statement I is true

(b) Only Statement II is true

(c) Both statements are true

(d) Both statements are false

**Answer**

B