Add whole numbers (written strategies) - No regrouping
Theory
To add whole numbers, line them up by place value and add each column, starting from the ones. When no column adds to ten or more, there is nothing to carry — this is addition without regrouping.
The column algorithm is a way to add numbers by writing them one under the other, lined up by place value.
Add each column from right to left — ones first, then tens, then hundreds — and write each total underneath.
When no column adds to ten or more, there is nothing to carry. This is addition without regrouping.
Setting out matters: every digit must sit in its own place-value column.
| Thousands | Hundreds | Tens | Ones |
|---|---|---|---|
| 4 | 1 | 2 | 3 |
| 2 | 5 | 3 | 4 |
| 6 | 6 | 5 | 7 |
How to add without regrouping
- Line up the numbers by place value, ones under ones.
- Add each column, starting from the ones on the right.
- Write each column total underneath to build the answer.
Add each column: \(2+5\), \(4+1\), \(3+2\).
| \(342 + 215\) | \(=\) | \(557\) |
No column reaches ten.
| \(4123 + 2534\) | \(=\) | \(6657\) |
The hundreds column is \(0+9=9\).
| \(6045 + 3902\) | \(=\) | \(9947\) |
| \(3204 + 2143\) | \(=\) | \(5347\) |
The total is \($5347\).
Common pitfalls
Frequently asked questions
How do you add large numbers?
Write them one under the other, ones under ones, and add each column from the right, writing each total underneath.
What does adding without regrouping mean?
No column adds to ten or more, so there is nothing to carry. \(4123 + 2534 = 6657\), with every column below ten.
Why start from the ones column?
Working right to left keeps each digit in place and builds the habit needed once carrying is required.
How do you line up numbers to add them?
By place value: ones under ones, tens under tens, hundreds under hundreds, keeping any zero in its own column.