77439636 divided by 129 
Our goal is to divide 77439636 by 129.

Let's proceed to step 1:
7 divided by 129 is 0 with a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 7 after subtracting 0 from 7.
Take the next digit (7) from the dividend and append it to 7, then repeat: 77 / 129

Step 2:
77 divided by 129 is 0 with a remainder of 77.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 77 to get 77.
Fetch the next digit (4) from the dividend, attach it to 77 and continue: 774 / 129

On to step 3:
The number 129 fits into 774 6 times, leaving a remainder of 0.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
The remainder is 0 after subtracting 774 from 774.
Include the next digit (3) from the dividend after 0, then repeat: 3 / 129

Step 4:
If we divide 3 by 129, we get 0 and a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 60.0
The remainder is 3 after subtracting 0 from 3.
Include the next digit (9) from the dividend after 3, then repeat: 39 / 129

Advancing to step 5:
The number 129 fits into 39 0 times, leaving a remainder of 39.
The number 0 becomes the next digit in our result. 
Result so far: 600.0
The remainder is 39 after subtracting 0 from 39.
Bring next digit (6) of the dividend behind the 39 and repeat the process: 396 / 129

Let's proceed to step 6:
The number 129 fits into 396 3 times, leaving a remainder of 9.
Write down 3 as next digit of the result. 
Result so far: 6003.0
If we take 387 away from 396, we end up with 9.
Bring next digit (3) of the dividend behind the 9 and repeat the process: 93 / 129

Going ahead to step 7:
129 goes into 93 0 times with a remainder of 93.
Use 0 as the next digit of our solution. 
Result so far: 60030.0
The remainder is 93 after subtracting 0 from 93.
Append the next digit (6) from the dividend to 93 and continue with: 936 / 129

Let's proceed to step 8:
If we divide 936 by 129, we get 7 and a remainder of 33.
Record the quotient 7 as the next digit in the result. 
Result so far: 600307.0
Subtracting 903 from 936 leaves us with 33.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

On to step 9:
The number 129 fits into 330 2 times, leaving a remainder of 72.
Write down 2 as next digit of the result. 
Result so far: 600307.2
If we subtract 258 from 330, we get 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Moving on to step 10:
720 divided by 129 is 5 with a remainder of 75.
Put 5 as the next digit of the answer. 
Result so far: 600307.25
If we take 645 away from 720, we end up with 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Advancing to step 11:
750 divided by 129 is 5 with a remainder of 105.
Use 5 as the next digit of our solution. 
Result so far: 600307.255
The remainder is 105 after subtracting 645 from 750.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1050, and continue the process.

After the division, we end up with 600307.255 and a remainder of 0.0105.