Proving Denumerability of Positive Multiples of Three Greater Than 100

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Homework Statement



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

Homework Equations


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?
 
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Why would you think it's not right? It is.
 
well its the first time I am taking an math class like this and I am just not sure if I am doing things right
 
eibon said:
well its the first time I am taking an math class like this and I am just not sure if I am doing things right

Well, you are doing it right.
 
Thanks for the reassurance
 

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