We look at the division of 86739370 by 129 
We want to figure out the number of times 86739370 can be divided by 129.

Advancing to step 1:
The number 129 fits into 8 0 times, leaving a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Append the next digit (6) from the dividend to 8 and continue with: 86 / 129

Going ahead to step 2:
When dividing 86 by 129, we get 0 with a remainder of 86.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 86, we end up with 86.
Include the next digit (7) from the dividend after 86, then repeat: 867 / 129

On to step 3:
129 goes into 867 6 times with a remainder of 93.
Write down 6 as next digit of the result. 
Result so far: 6.0
The remainder is 93 after subtracting 774 from 867.
Include the next digit (3) from the dividend after 93, then repeat: 933 / 129

Moving on to step 4:
933 divided by 129 is 7 with a remainder of 30.
The number 7 becomes the next digit in our result. 
Result so far: 67.0
If we subtract 903 from 933, we get 30.
Bring next digit (9) of the dividend behind the 30 and repeat the process: 309 / 129

Step 5:
129 can be fit into 309 2 times, resulting in a remainder of 51.
The number 2 becomes the next digit in our result. 
Result so far: 672.0
If we subtract 258 from 309, we get 51.
Take the next digit (3) from the dividend and append it to 51, then repeat: 513 / 129

Moving on to step 6:
513 divided by 129 is 3 with a remainder of 126.
Use 3 as the next digit of our solution. 
Result so far: 6723.0
Deduct 387 from 513 and we're left with 126.
Grab the next digit (7) from the dividend, add it to 126, then carry on: 1267 / 129

Let's proceed to step 7:
The number 129 fits into 1267 9 times, leaving a remainder of 106.
Use 9 as the next digit of our solution. 
Result so far: 67239.0
The remainder is 106 after subtracting 1161 from 1267.
Fetch the next digit (0) from the dividend, attach it to 106 and continue: 1060 / 129

Step 8:
When dividing 1060 by 129, we get 8 with a remainder of 28.
The next digit of our result is 8. 
Result so far: 672398.0
The remainder is 28 after subtracting 1032 from 1060.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

On to step 9:
When dividing 280 by 129, we get 2 with a remainder of 22.
Write down 2 as next digit of the result. 
Result so far: 672398.2
If we subtract 258 from 280, we get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Step 10:
129 goes into 220 1 times with a remainder of 91.
Use 1 as the next digit of our solution. 
Result so far: 672398.21
Deduct 129 from 220 and we're left with 91.
Since there are no more digits in the dividend, we add a zero to the remainder making it 910, and continue the process.

Advancing to step 11:
910 divided by 129 is 7 with a remainder of 7.
Use 7 as the next digit of our solution. 
Result so far: 672398.217
Subtracting 903 from 910 leaves us with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Advancing to step 12:
129 goes into 70 0 times with a remainder of 70.
The number 0 becomes the next digit in our result. 
Result so far: 672398.217
If we take 0 away from 70, we end up with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

On to step 13:
If we divide 700 by 129, we get 5 and a remainder of 55.
The next digit of our result is 5. 
Result so far: 672398.21705
If we take 645 away from 700, we end up with 55.
Since there are no more digits in the dividend, we add a zero to the remainder making it 550, and continue the process.

Going ahead to step 14:
129 goes into 550 4 times with a remainder of 34.
Write down 4 as next digit of the result. 
Result so far: 672398.217054
If we subtract 516 from 550, we get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Going ahead to step 15:
129 can be fit into 340 2 times, resulting in a remainder of 82.
Put 2 as the next digit of the answer. 
Result so far: 672398.2170542
Subtracting 258 from 340 leaves us with 82.
Since there are no more digits in the dividend, we add a zero to the remainder making it 820, and continue the process.

Let's proceed to step 16:
129 goes into 820 6 times with a remainder of 46.
The number 6 becomes the next digit in our result. 
Result so far: 672398.21705426
Subtracting 774 from 820 leaves us with 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

Our division results in 672398.21705426 with a remaining 4.6e-08.