Practice Questions on Sets

1.    Roster form of set is
    (a)    Writing all the objects together one after another
    (b)    Writing some of the objects
    (c)    Writing all the objects separated by commas and then enclosing all of them within one curly bracket
    (d)    Mentioning the property satisfied by all objects
Ans. (c)
2.    Set Builder form of the set {1, 3, 5, 7, 9} is
    (a)    {x : x is odd natural number and less than 10}
    (b)    {x : x is natural number}
    (c)    {x : x = 2n + 3, n is natural number less than 3}
    (d)    None of these
Ans. (a)
3.    If every element of set A is also an element of set B then
    (a)    A is subset of B   
    (b)    B is subset of A
    (c)    B is Null set   
    (d)    A and B are equal sets
Ans. (a)
4.    Power set contains
    (a)    all elements given powers
    (b)    all sets
    (c)    no element
    (d)    only one element
Ans. (b)
    As power set is set of subsets of given set.
5.    Universal set is
    (a)    Super set of all the sets under consideration
    (b)    Subset of all the sets under consideration
    (c)    a set with no element
    (d)    Proper subset of all the sets
Ans. (a)
    Universal set contains all the elements/numbers/objects under consideration.
6.    A man has 10 friends. In how many ways he can invite one or more of them to a party
    (a)    10!       
    (b)    210
    (c)    10! – 1   
    (d)    210 – 1
Ans. (d)
7.    Two finite sets have m and n elements. The number of elements in the power set of 1st set is 48 more than the total number of elements in power set of second set. The value of m and n are
    (a)    7, 6       
    (b)    6, 3
    (c)    6, 4       
    (d)    7, 7
Ans. (c)
8.    Out of 1000 families investigated, 800 families own Maruti car, 400 families own Santro car, 100 own both the cars, then how many own not even a single car
    (a)    100      
    (b)    200
    (c)    300      
    (d)    None of these
Ans. (d)