## ML Aggarwal Class 7 Solutions for ICSE Maths Chapter 5 Sets Ex 5.1

Question 1.

State which of the following collections are set:

(i) All states of India.

(ii) Four cities of India having more than one lac population.

(iii) All tall students of your school.

(iv) Four colours of a rainbow.

(v) All the beautiful flowers.

(vi) All clever people of Lucknow.

(vii) Last three days of a week.

(viii)All months of a year having at least 30 days.

Solution:

Question 2.

Let A = {vowels of English alphabet}, then which of the following statements are true. In case a statement is incorrect, mention why.

(i) c ∈ A

(ii) {a} ∈ A

(iii) a, i, u, ∈ A

(iv) {a, u} ∉ A

(v) {a, i, u } ∈ A

(vi) a, b, ∈ A

Solution:

Question 3.

Describe the following sets:

(i) {a, b, c, d, e, f}

(ii) {2, 3, 5, 7, 11, 13, 17, 19}

(iii) {Friday, Saturday, Sunday}

(iv) {April, August, October}

Solution:

Question 4.

Write the following sets in tabular form and also in set builder form:

(i) The set of even whole numbers which lie between 10 and 50.

(ii) {months of a year having more than 30 days}

(iii) The set of single-digit whole numbers which are a perfect square.

(iv) The set of factors of 36.

Solution:

Question 5.

Write the following sets in roster form and also in description form:

(i) {x | x = 4n, n ∈ W and n < 5}

(ii) {x : x = n^{2}, n ∈ N and n < 8}

(iii) y : y = 2x – 1, x ∈ W and x < 5}

(iv) {x : x is a letter in word ULTIMATUM}

Solution:

Question 6.

Write the following sets in roster form:

(i) {x | x ∈ N, 5 ≤ x < 10 }

(ii) {x | x = 6 p, p ∈ I and – 2 ≤ p ≤ 2}

(iii) {x | x = n^{2} – 1, n ∈ N and n < 5}

(iv) {x | x – 1 = 0}

(v) {x | x is a consonant in word NOTATION}

(vi) {x | x is a digit in the numeral 11056771}

Solution:

Question 7.

Write the following sets in set builder form:

(i) (1, 3, 5, 7, …….. 29}

(ii) {2, 3, 5, 7, 11, 13, 17, 19, 23, 29}

(iii) {1, 4, 9, 16, 25, ………}

(iv) {\(\frac { 1 }{ 5 }\), \(\frac { 1 }{ 6 }\), \(\frac { 1 }{ 7 }\), …… \(\frac { 1 }{ 20 }\)}

(v) {-16, -8, 0, 8, 16, 24, 32, 40}

(vi) {January, June, July}

Solution:

Question 8.

If V is the set of vowels in the word COMPETITION, write the given set in

(i) description form

(ii) set builder form

(iii) roster form

Solution: