Question

A= {x:x is a positive multiple of 3 less than 20} and B={x:x is an odd prime no. less than 20} then find (n)A+(n)B

plz answer I have a test in an hour​

Answer 1

Step-by-step explanation:

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

⟹S={3,6,9,12,⋯,99}

⟹n(S)=33

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

MAY HELP YOU

Answer 2

but man this answer is fake the real answer will be 13