To find the sum of the numbers 645, 287, and 413, we will follow these steps:
### Step 1: Write the numbers in a column format
```
645
+ 287
+ 413
```
### Step 2: Add the digits in the units place (rightmost column)
- The units digits are 5 (from 645), 7 (from 287), and 3 (from 413).
- Calculation: 5 + 7 = 12, then 12 + 3 = 15.
- Write down 5 and carry over 1 to the next column.
### Step 3: Add the digits in the tens place (second column from the right)
- The tens digits are 4 (from 645), 8 (from 287), and 1 (from 413), plus the carry over of 1.
- Calculation: 4 + 8 = 12, then 12 + 1 (carry) = 13.
- Write down 3 and carry over 1 to the next column.
### Step 4: Add the digits in the hundreds place (third column from the right)
- The hundreds digits are 6 (from 645), 2 (from 287), and 4 (from 413), plus the carry over of 1.
- Calculation: 6 + 2 = 8, then 8 + 4 = 12, and finally 12 + 1 (carry) = 13.
- Write down 3 and carry over 1, which will be placed in the next column.
### Step 5: Write down the final carry over
- Since we have a carry over of 1, we write it down in the next column to the left.
- This gives us the final sum.
### Final Result
Putting it all together, we have:
```
645
+ 287
+ 413
------
1345
```
So, the sum of 645, 287, and 413 is **1345**.
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