7438855541-568846756

To solve the subtraction problem 7438855541 - 568846756, we will perform the arithmetic step by step.

First, we align the numbers vertically to make subtraction easier:

```
7438855541
- 568846756
-------------
```

Starting from the rightmost digit:

1. In the first column (rightmost), we have 1 - 6. Since 1 is less than 6, we need to borrow from the next column. This converts the 4 into a 3 and the 1 into 11. So, 11 - 6 = 5.

2. In the second column, we now have 3 (after borrowing) to subtract from. So, we do 3 - 5. Again, 3 is less than 5, so we borrow from the next column. This turns 5 into 4 and makes the 3 into 13. Thus, 13 - 5 = 8.

3. In the third column, we subtract 4 (left after borrowing) from 7. 4 - 7 requires borrowing again. We turn 8 into 7, making the 4 into 14. So, 14 - 7 = 7.

4. In the fourth column, we have 7 (from 7 after borrowing) and we subtract 8. This requires another borrowing. We take from the 3, turning it into 2 and the 7 into 17. Thus, 17 - 8 = 9.

5. In the fifth column, we subtract 2 (after borrowing) - 4. This also requires borrowing. We take from the 8, turning it into 7 and the 2 into 12. So, 12 - 4 = 8.

6. In the sixth column, we have 7 - 6 = 1.

7. In the seventh column, we have 4 - 8. Again we need to borrow. We take from the 4, making it a 3 and the 4 becomes 14. Therefore, 14 - 8 = 6.

8. In the eighth column, we have 3 - 6. We need to borrow from the 7, turning it into a 6 and the 3 becomes 13. Thus, 13 - 6 = 7.

9. In the ninth column, we have 6 - 5 = 1.

10. Finally, in the leftmost column, we have 7 - nothing = 7.

Writing it all together, we get:

```
7438855541
- 568846756
-------------
6870008785
```

So, the final answer is 6870008785.