Thread: ordered pairs question

if a b c are three natural numbers in Arithmetic progression and a+b+c=21 then all the possible values of the ordered triplet (a,b,c) is

If they are in arithmetric progression, a, b and c have a common difference, or:



Then;



I think that should be okay to solve now.

Originally Posted by prasum

if a b c are three natural numbers in Arithmetic progression and a+b+c=21 then all the possible values of the ordered triplet (a,b,c) is

Your AP is so .
That means that .
The numbers of pairs that satisfy that depends on if we consider 0 a natural or not.

Here is an example: then the AP is .

Can you finish?