## ML Aggarwal Class 7 Solutions for ICSE Maths Chapter 5 Sets Ex 5.2

Question 1.

Classify the following sets into empty set, finite set and infinite set. In case of (non-empty) finite sets, mention the cardinal number.

(i) {all colours of a rainbow}

(ii) {x | x is a prime number between 7 and 11}

(iii) {multiples of 5}

(iv) {all straight lines drawn in a plane}

(v) {x | x is a digit in the numeral 550131527}

(vi) {x | x is a letter in word SUFFICIENT}

(vii) {x | x = 4n, n ∈ I and x < 10}

(viii) {x | x ∈ N, x is a prime factor of 180}

(ix) {x : x is a vowel in the word WHY}

(x) {x : x = 5n, n ∈ W and x < 60}

Solution:

Question 2.

Which of the following describe the same sets:

(i) {vowels of English alphabet} and {e, a, u, i, o}

(ii) {a, b, d} and {d, a, b, b}

(iii) {letters of PUPPET} and {E, T, P, U}

(iv) {1, 2, 3} and {2, 3, 4}

(v) {1, 2, 3, 4, 5} and {x | x ∈ N, x ≤ 5}

Solution:

Question 3.

Find pairs/groups of equal sets from the following sets:

A = {0, 1, 2, 3}

B = {x : x^{2} < 10, x ∈ W}

C = {letters of word FOLLOW}

D = {days of a week}

E = {x | x ∈ W, x < 4}

F = {letters of word FLOW}

G = {Monday, Tuesday, ……… , Sunday}

H = {letters of word WOLF}

Solution:

Question 4.

Find pairs/groups of equivalent sets from the following sets.

A = {colours of a rainbow}

B = {letters of word GOOD}

C = {x : x is a digit in the numeral 371011489}

D = {letters of word TOM}

E = {x : x ∈ I, x^{2} < 10}

F = {months of a year}

G = {days of a week}

H = {x | x = 3n, n ∈ W and n < 12}

I = {all even numbers between 1 and 53}

J = {all letters of English alphabets}

Solution:

Question 5.

In the following, find whether A ⊂ B or B ⊂ A or none of these:

(i) A = { 1, 2, 3}, B = {2, 3, 3, 3, 1, 3}

(ii) A = {2, 4, 6,….}, B = {all natural numbers}

(iii) A = {x | x ∈ I, x^{2} < 20}, B = {0, 1, 2, 3, 4}

(iv) A = {letters of KING},

B = {letters of QUEEN}

Solution:

Question 6.

State whether each of the following statement is true or false for the sets A and B where

A = {letters of CLOUD} and B = {letters of KOLKATA}

(i) A ⊂ B

(ii) B ⊂ A

(iii) A ↔ B

Solution:

Question 7.

Write all the subsets of the following sets:

(i) Φ

(ii) {3, 5}

(iii) {2, 4, 6}

Solution:

Question 8.

If A = {x : x = 2n, n < 5}, then find A when

(i) ξ = N

(ii) ξ = W

(iii) ξ = I

Solution: