Vertically align numbers with Larger Number on top:
| 4 | 2 | |
| − | 2 | 5 |
Subtract using place value:
| Tens | Ones | |
|---|---|---|
| 3 | 12 | |
| 42 | 4 | 2 |
| 25 | 2 | 5 |
| Difference | 1 | 7 |
Column traversal from right to left
Ones column:
Ones column:
- Since 2 is less than 5, we have to borrow 1 from the Tens column
- As a result, 2 becomes 12, and 12 − 5 = 7
- The 4 in the Tens column becomes 3
Tens column:
- 3 − 2 = 1
| 3 | 12 | |
| 4 | 2 | |
| − | 2 | 5 |
| 1 | 7 |
Therefore, the Difference between 42 and 25 is 17
Check computation by comparing Larger Number and the Sum of Smaller Number and Difference:
| 1 | ||
| 2 | 5 | |
| 1 | 7 | |
| 4 | 2 |
Sum of Smaller Number and Difference = 42
Sum of Smaller Number and Difference = Larger Number (42 = 42) ✓
