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jenniferjuice
If C = {integers divisible by 6 from 1 to 30} and D = {integers divisible by 3 from 1 to 20}, what is C ∩ D?
C ∩ D means C intersect D in other words its the set of elements which are members of both C and D.
the easiest way to do this is to list all the elements in C and D
C = {6, 12, 18, 24, 30} now list D and compare with C