We look at the division of 68580656 by 129 
We want to divide 68580656 by 129.

Advancing to step 1:
The number 129 fits into 6 0 times, leaving a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Grab the next digit (8) from the dividend, add it to 6, then carry on: 68 / 129

Moving on to step 2:
129 can be fit into 68 0 times, resulting in a remainder of 68.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 68 and we're left with 68.
Append the next digit (5) from the dividend to 68 and continue with: 685 / 129

Step 3:
If we divide 685 by 129, we get 5 and a remainder of 40.
The next digit of our result is 5. 
Result so far: 5.0
The remainder is 40 after subtracting 645 from 685.
Append the next digit (8) from the dividend to 40 and continue with: 408 / 129

Advancing to step 4:
When dividing 408 by 129, we get 3 with a remainder of 21.
The next digit of our result is 3. 
Result so far: 53.0
Subtract 387 from 408 to get 21.
Append the next digit (0) from the dividend to 21 and continue with: 210 / 129

Moving on to step 5:
129 goes into 210 1 times with a remainder of 81.
The next digit of our result is 1. 
Result so far: 531.0
Subtracting 129 from 210 leaves us with 81.
Append the next digit (6) from the dividend to 81 and continue with: 816 / 129

Advancing to step 6:
When dividing 816 by 129, we get 6 with a remainder of 42.
Record the quotient 6 as the next digit in the result. 
Result so far: 5316.0
The remainder is 42 after subtracting 774 from 816.
Bring next digit (5) of the dividend behind the 42 and repeat the process: 425 / 129

Advancing to step 7:
The number 129 fits into 425 3 times, leaving a remainder of 38.
The next digit of our result is 3. 
Result so far: 53163.0
If we subtract 387 from 425, we get 38.
Take the next digit (6) from the dividend and append it to 38, then repeat: 386 / 129

Moving on to step 8:
If we divide 386 by 129, we get 2 and a remainder of 128.
The number 2 becomes the next digit in our result. 
Result so far: 531632.0
Subtract 258 from 386 to get 128.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1280, and continue the process.

On to step 9:
129 can be fit into 1280 9 times, resulting in a remainder of 119.
Put 9 as the next digit of the answer. 
Result so far: 531632.9
If we subtract 1161 from 1280, we get 119.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1190, and continue the process.

Step 10:
1190 divided by 129 is 9 with a remainder of 29.
The number 9 becomes the next digit in our result. 
Result so far: 531632.99
If we take 1161 away from 1190, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

The final result is 531632.99 with a remainder of 0.029.