Question

The sum of consecutive odd numbers is 69 what is the third number in this sequence?

Answer 1

You haven't actually told us HOW MANY consecutive odd numbers.

If there are three (3) of them, then they are 21, 23, and 25,
and the third one is 25.

Oh !  I think there MUST be three of them.  That's the only way
they can all be whole numbers.