Vertically align numbers with Larger Number on top:
7 | 8 | |
− | 4 | 2 |
Subtract using place value:
Tens | Ones | |
---|---|---|
78 | 7 | 8 |
42 | 4 | 2 |
Difference | 3 | 6 |
Column traversal from right to left
Ones column:
Ones column:
- 8 − 2 = 6
Tens column:
- 7 − 4 = 3
7 | 8 | |
− | 4 | 2 |
3 | 6 |
Therefore, the Difference between 78 and 42 is 36
Check computation by comparing Larger Number and the Sum of Smaller Number and Difference:
4 | 2 | |
3 | 6 | |
7 | 8 |
Sum of Smaller Number and Difference = 78
Sum of Smaller Number and Difference = Larger Number (78 = 78) ✓