When a column adds up to more than 9, it won't fit in one digit, so you trade: ten ones become one ten. Subtracting uses the same trade backward. If you don't have enough ones, you break a ten into ten ones.
That's what "carrying" and "borrowing" really are. Nothing is lost. You've just rewritten the same amount.
Work through it
Ones: . Keep 3, and trade ten ones for one ten.write 3, carry 1
Tens: . Keep 4, and trade ten tens for one hundred.write 4, carry 1
Hundreds: .
Ones: you can't take 8 from 3, and the tens place has 0. Borrow from the hundreds first. becomes hundreds and tens
Now borrow a ten for the ones. tens and ones
Subtract each place: , , .
Check with addition.
Subtraction undoes addition, so the answer plus what you took away must give the start.
Watch out for this
, by subtracting the smaller digit from the bigger one in each column.
You can't flip a column. The ones are , so borrow: , then . The answer is .
Line up the places and start with the ones. Ten in one place trades for one in the next. To subtract, borrow one and it becomes ten.
Your turn
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