# Types of Set

1. {x: x is an integer neither positive nor negative} is ________
a) Empty set
b) Non-empty set
c) Finite set
d) Non- empty and Finite set

2. {x: x is a real number between 1 and 2} is an ________
a) Infinite set
b) Finite set
c) Empty set
d) None of the mentioned

3. Write set {1, 5, 15, 25,…} in set-builder form.
a) {x: either x=1 or x=5n, where n is a real number}
b) {x: either x=1 or x=5n, where n is a integer}
c) {x: either x=1 or x=5n, where n is an odd natural number}
d) {x: x=5n, where n is a natural number}

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4. Express {x: x= n/ (n+1), n is a natural number less than 7} in roster form.
a) {12234567}
b) {12233445566778}
c) {122334455667}
d) Infinite set

5. Number of power set of {a, b}, where a and b are distinct elements.
a) 3
b) 4
c) 2
d) 5

Explanation: Power set of {a, b} = {∅, {a, b}, {a}, {b}}.

6. Which of the following is subset of set {1, 2, 3, 4}?
a) {1, 2}
b) {1, 2, 3}
c) {1}
d) All of the mentioned

Explanation: There are total 16 subsets.

7. A = {,{},2,{2,},3}, which of the following is true?
a) {{∅,{∅}} ∈ A
b) {2} ∈ A
c) A
d) 3 ⊂ A
Explanation: Empty set is a subset of every set.

8. Subset of the set A= { } is?
a) A
b) {}
c) ∅
d) All of the mentioned

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9. {x: x N and x is prime} then it is ________
a) Infinite set
b) Finite set
c) Empty set
d) Not a set

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10. Convert set {x: x is a positive prime number which divides 72} in roster form.
a) {2, 3, 5}
b) {2, 3, 6}
c) {2, 3}
d) {∅}