# A denumerable question

1. Sep 26, 2010

### eibon

1. The problem statement, all variables and given/known data

Let S be the set of positive multiples of three which are greater than one hundred.
Show that S is denumerable.

2. Relevant equations

3. The attempt at a solution
let $$\phi$$: $$N$$ $$\rightarrow$$ S
be given by $$\phi$$(n)= 99+3n is a bijection
thus it is denumerable

can someone tell me if that is right? if not can you tell me what i did wrong?

2. Sep 26, 2010

### Dick

Why would you think it's not right? It is.

3. Sep 26, 2010

### eibon

well its the first time im taking an math class like this and im just not sure if im doing things right

4. Sep 26, 2010

### Dick

Well, you are doing it right.

5. Sep 26, 2010

### eibon

Thanks for the reassurance