Q42 of 58 Page 12

Let S = {x | x is a positive multiple of 3 less than 100}

P = {x | x is a prime number less than 20}. Then n(S) + n(P) is

Given: S = {x | x is a positive multiple of 3 less than 100} and P = {x | x is a prime number less than 20}


To find: n(S) + n(P)


S = {x | x is a positive multiple of 3 less than 100}


⇒ S = {3, 6, 9, 12, 15,……, 99}



P = {x | x is a prime number less than 20}


⇒ P = {2, 3, 5, 7, 11, 13, 17, 19}


⇒ n(P) = 8


n(S) + n(P) = 33 + 8 = 41


Hence, answer is 41

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Fill in the blanks

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