Math
posted by Jen on .
Using correct mathematical notation and symbols, express the following in setbuilder notation:
Z = {16, 17, 18, 19, 20}
I'm so confused with this....please help :(

do it the same way I just showed you in the other post.
the numbers are between 15 and 20, and they are natural numbers. 
{x  15 < x < 20, x ∈ N} ??

or would it be this {x  15 < x < 20, x ∈ z} ???

That would work, except say 15<x<21, that was my error.
I would use x ∈ N , since the numbers 15 and 20 were not part of the set Z
or you could say
{x  16 ≤ x ≤ 20, x ∈ z}
btw, I should have had the original above as
{x  15 < x < 21, x ∈ N}
The way I had it, the 20 would have been excluded. 
So your saying this question:
Express the following in roster form: Set M is the set of natural numbers between fourteen and nineteen, would be
{x  15 < x < 21, x ∈ N} ?? 
Please read my replies above including the correction
you want the numbers 16,17,18,19,20
they can be expressed
either as
16≤x≤20 , x∈N
or
15<x<21, x∈N