Practice long addition with carrying and long subtraction with borrowing, one column at a time. Choose a problem and begin your step-by-step practice.
Non-negative whole numbers only. Up to 8 digits per number.
Select Addition or Subtraction, then enter two non-negative whole numbers.
Choose Start Addition or Start Subtraction to set up the numbers vertically.
Follow the prompt, do the current calculation, and enter your answer before moving on.
Show Me One Step completes only the step you are on, so you can continue the rest of the problem yourself.
In long addition, begin in the ones column and move left. For 478 + 256, first add 8 + 6. The answer is 14, so write 4 in the ones place.
When a column makes a two-digit total, the Tutor shows the carry as its own next step. First calculate the two digits in the current column; if the previous column made a carry, handle that carry separately when the Tutor asks. This keeps place value clear and helps students see why 478 + 256 = 734.
The Tutor does not jump straight to the final answer. It guides you through each addition and carry so you can do the thinking.
In long subtraction, start at the ones column. When the top digit is too small to subtract the bottom digit, choose Borrow 1. Borrowing is also called regrouping, but this Tutor uses the clear action name Borrow 1.
After you borrow, the current column receives ten more ones. The column that lent the ten has a small −1 above it. Finish the current column first. When you move left, the Tutor asks you to deal with that −1 before you do the normal subtraction in the new column.
This one-column-at-a-time order makes each change visible. It is especially useful when a zero appears in a subtraction problem.
Try 1204 − 38. Write 38 as 0038 so the places line up. The ones column, 4 − 8, needs a borrow. Choose Borrow 1, finish 14 − 8 = 6, and leave the small −1 above the tens column.
14 − 8 = 6
The ones column borrows and is completed first.
0 − 1 needs a borrow
9 − 3 = 6
Handle the −1, then subtract in the tens column.
0 − 1 needs a borrow
9 − 0 = 9
Again, settle the −1 before the normal subtraction.
1 − 1 = 0
0 − 0 = 0
The leftmost column finishes after its −1 is handled.
The answer is 1166. The Tutor does not treat this as one big borrow from the thousands place to the ones place. Instead, it shows the borrowing work one column at a time.
This Tutor supports standard vertical addition and subtraction practice without giving away the whole answer. Students work through carrying and borrowing in the order they happen, while prompts keep attention on the current column.
Use it for a short class demonstration, guided small-group practice, or independent work at home. Ask students to say why they carried or borrowed before they enter the next answer.
It guides students through every needed column, including carries in addition and borrowing steps in subtraction. Students still enter the work themselves.
Carrying happens when a column total is 10 or more. You write the ones digit in the current column and use the remaining ten in the next column.
Borrowing means taking one ten, hundred, or larger place from the column to the left so the current column has enough to subtract.
Yes. Both words describe changing a value into equivalent place-value parts. This Tutor calls the action Borrow 1.
Yes. The Tutor handles it one column at a time, including the small −1 that must be handled in the next column.
Each number can have up to eight digits.
It completes only the current step. It does not solve the entire problem for you.
No. This version supports non-negative whole numbers only; decimals and negative numbers are not supported.
The NDED Long Addition and Subtraction Tutor is a free interactive tool for practicing vertical arithmetic step by step. Students choose long addition with carrying or long subtraction with borrowing, then complete each column instead of simply receiving the answer.
An ordinary calculator gives a result right away. The NDED Tutor is for practice: students complete the carrying and borrowing steps themselves, one column at a time, with help available for only the current step.