Subject Experts Solutions for Chapter: Set Theory, Exercise 1: PRACTICE QUESTIONS (CLASSROOM WING)

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Subject Experts Mathematics Solutions for Exercise - Subject Experts Solutions for Chapter: Set Theory, Exercise 1: PRACTICE QUESTIONS (CLASSROOM WING)

Attempt the free practice questions on Chapter 10: Set Theory, Exercise 1: PRACTICE QUESTIONS (CLASSROOM WING) with hints and solutions to strengthen your understanding. Pearson IIT Foundation Mathematics solutions are prepared by Experienced Embibe Experts.

Questions from Subject Experts Solutions for Chapter: Set Theory, Exercise 1: PRACTICE QUESTIONS (CLASSROOM WING) with Hints & Solutions

EASY
7th CBSE
IMPORTANT

If O={1}, then find the number of all possible proper subsets of O.

EASY
7th CBSE
IMPORTANT

If N={a,b,c,...z}, then find all the possible subsets of N.

EASY
7th CBSE
IMPORTANT

If n(A)=20, n(AB)=10 and n(AB)=70, then find n(B).

EASY
7th CBSE
IMPORTANT

If X={0,1,2,3,4,5,6,7,8,9,10} and Y={2,4,6,8,10}, then find X-Y.

MEDIUM
7th CBSE
IMPORTANT

The mean of 36 observations is 22. If one observation 22 is deleted, then find the new mean.

The following steps are involved in solving the above problem. Arrange them in sequential order.

(A)New arithmetic mean =77035=22

(B) Arithmetic mean =The sum of observationsTotal number of the observations22=The sum of observations36

(C) The sum of observations =36×22=792

(D) Since one observation 22 is deleted, the new sum =792-22=770 and the number of observation is 36-1 i.e., 35.

EASY
7th CBSE
IMPORTANT

If A={x:xW, x10} and B={x:xN, x10}, then find n(AB).

The following steps are involved in solving the above problem. Arrange them in the sequential order.

(A) n(AB)=11

(B) AB={0,1,2,3,4,5,6,7,8,9,10}{1,2,3,4,5,6,7,8,9,10}

(C) From the given data A={0,1,2,3,4,5,6,7,8,9,10} and B={1,2,3,4,5,6,7,8,9,10}

(D) AB={0,1,2,3,4,5,6,7,8,9,10}

EASY
7th CBSE
IMPORTANT

The mean of 2,12,x,15,20 and 17 is 16, then find the value of x.

The following steps are involved in solving the above problem. Arrange them in sequential order.

(A) 16=2+12+x+15+20+176

(B) 96=66+x

(C) x=96-66=30

(D) We have arithmetic mean 

=The sum of observations Total number of observations

EASY
7th CBSE
IMPORTANT

In a class there are 100 students. Of them, 60 students attend music classes, 40 students attend dance classes, and 20 students attend both the classes. Find the number of students who attend neither of the classes. 

The following steps are involved in solving the above problem. Arrange them in sequential order.

(A) 

 n(MD)=n(M)+n(D)-n(MD)n(MD)=60+40-20=100-20=80

(B) Number of students who attend neither of the classes =100-80=20

(C) n(M)=60, n(D)=40 and n(MD)=20 (given)

(D) Let n(M) be the number of students who attend music classes n(D) be the number of students who attend dance classes.