Regrouping Tens as Ones (Borrowing): 3 Digit Numbers
Regrouping the tens place as ones simply means that we are taking one group of ten from the tens place and grouping (adding) it with the one's place. In other words, if the bottom number is bigger in the one's place we need to change the problem in order to solve it. Those of us who went to elementary school in the 50's, 60's and 70's learned this as "borrowing," however, textbooks today refer to this process as "regrouping." The key here is that the student must know when or when not to "regroup" or "borrow." As simple a concept as this may seem, students seem to have a difficult time knowing when to regroup. Over the years we at MathKEY have found a fun and very effective technique to teach students when to "regroup" when doing subtraction. We highly recommend that your student ask him or herself this question whenever subtracting a column in a subtraction problem - "IS THE BOTTOM NUMBER BIGGER?" If the answer is "no" then then just subtract, if the answer is "yes" then they must "borrow from the baby" (and the baby resides in the column to the left). The uniqueness and humor in this phrase actually does an excellent job in helping students remember and follow the correct procedure..
Solve the subtraction problem.