Long addition is used to add large numbers by combining two numbers into a single quantity, called a sum.

## How to do the long addition:

- Step 1: Write the numbers you want to add, one underneath the other.
- Step 2: Add up the numbers in the right-most column.
- Step 3: Check if the answer from the previous step is 9 or less:

if yes, write the number below the column (between the lines) and move to Step 4.

if no, the answer will have two digits. Write the digit on the right under the column (between the lines). Write the digit on the left under the column to the left of the current column (below the two lines). Move to Step 4.

- Step 4: Move to the column to the left. Add up the numbers in this column, including any numbers below the two lines.
- Step 5: Go to Step 3 and repeat until all columns have been added.

### Example:

Add 327 and 184.

### Solution:

Step1:
Add up the numbers in the right-most column.

7 + 4 = 11

Step2:
Check if the answer from the previous step is 9 or less:

11 is not 9 or less, so the answer will have two digits. Write the digit on the right under the column (between the lines).

Write the digit on the left underneath the column to the left of the current column (below the two lines).

‘Carry’ the 1.
Move to the next step.

Step3:
Move to the column to the left. Add up the numbers in this column, including any numbers below the two lines.

Step4:
Now, you have to repeat the algorithm until all the columns are added up.

Check if the answer from the previous step is 9 or less.

No. 11 is not 9 or less. So, write the digit on the right underneath the column (between the lines).

Write the digit on the left underneath the column to the left of the current column (below the two lines).

‘Carry’ the 1.
Move to the next step.

Step5:
Move to the column to the left. Add up the numbers in this column, including any numbers below the two lines.

3 + 1 + 1 = 5

Step6:
Check if the answer from the previous step is 9 or less. As 5 is less than 9, write the number below the column (between the lines):

All columns have been added.

Answer: 511