math
posted by Alex .
juan says,"When you put together unequal groups, you can only add." is he correct? Explain

Depends on what you mean by "put together" and "groups".
If you "put together" the even numbers and the odd numbers, you might get all integers.
If you "out together" positive and negative numbers, maybe you just get 0.
If you put together apples and oranges, you get a fruit basket.
If you put together zealots and infidels, you get a war.
and so on. 
Yes