If W = {positive integers} and subset Z = {positive integers divisible by 5}, what is Z′?

{1, 2, 3, 4, …}

{ }

{5, 10, 15, 20, …}

{1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 13, 14, 16, …}

Question

If W = {positive integers} and subset Z = {positive integers divisible by 5}, what is Z′?

{1, 2, 3, 4, …}

{ }

{5, 10, 15, 20, …}

{1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 13, 14, 16, …}

kainui · Answer

That little mark there means "Not Z". So what's not Z on that list?

anonymous · Answer

{1, 2, 3, 4, …}?

kainui · Answer

Nope, because that one shows that you keep counting to 5,6,7,8,9,10 and 5 and 10 are Z. So look down the list a little more.

anonymous · Answer

then it has tobe this one??     {1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 13, 14, 16, …}

kainui · Answer

Yeah, right on the money. No 5, 10, 15 in there at all, makes sense yeah not so bad huh?

anonymous · Answer

yea, thanks