MATHS MCQ

A = {x | x is a positive mutliple of 3 less than 20}
= {3, 6, 9, 12, 15, 18} ⇒ n(A) = 6
B = {x | x is a prime number less than 20}
= {2, 3, 5, 7, 11, 13, 17, 19} ⇒ n(B) = 8
n(A) + n(B) = 6 + 8 = 14 (d)

The cardinal number n(A) = {x : x is an odd prime number less than 20}
= {3, 5, 7, 11, 13, 17, 19}
n( A) = 7 (b)

Empty set is denoted as { }. (b)

The symbol ↔ stands for is equivalent to. (c)

Set with a limited number of distinct elements is called a finite set. (a)

Days of the week starting with the letter T in tabular form is {Tuesday, Thursday}. (b)

Collection of 5 odd prime number, Collection of 4 vowels of English alphabet and collection of first 6 months of a year, all are sets but a collection of 3 most intelligent students of your class is not a set, because intelligence is not well defined. (b)