Regrouping: Regrouping is the process used in addition in subtraction that most of us remember being known as "carrying" and "borrowing."
In addition, for example, a problem such as 19 + 3 would require us to "carry" 1 from the ones place (because 9 +3 =12) to the tens place. Since this numeral really represents the number 10, it's more appropriate to say we've regrouping it by putting those ten ones into one ten.
The same process works in reverse in subtraction. Instead of "borrowing" one from the ten's place, we regroup that ten into ten ones.
Also Known As: carrying, borrowing