Thread: Help is needed with two regrouping questions, PLEASE

FirstQuestion: Write 3 different ones numbers you could add to 15 without needing to regroup.

Second Question: Write 3 different ones numbers you could add to 15 where you need to regroup to find the sum.

what, exactly, do you mean by "regroup"

I can't really understand the question itself.

Define "ones" and "regroup", hoping you know what it's about.