Question

If C = {integers divisible by 2 from 1 to 20} and D = {integers divisible by 6 from 1 to 25}, what is C ∩ D?

{2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 24}

{6, 12, 18}

{6, 12, 18, 24}

{ }

Answer 1

C ∩ D refers to integers divisible by both 2 &6 which lie between 1 to 20.thus it is 6,12,18

Answer 2

C={2,4,6,8,10,12,14,16,18,20}
D={6,12,18}
C ∩ D is the set containing elements common to both C and D.
Thus
C ∩ D={6,12,18}