We look at the division of 639966 by 77 
We want to figure out the number of times 639966 can be divided by 77.

Advancing to step 1:
6 divided by 77 is 0 with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Fetch the next digit (3) from the dividend, attach it to 6 and continue: 63 / 77

On to step 2:
77 goes into 63 0 times with a remainder of 63.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 63, we end up with 63.
Append the next digit (9) from the dividend to 63 and continue with: 639 / 77

Step 3:
The number 77 fits into 639 8 times, leaving a remainder of 23.
Put 8 as the next digit of the answer. 
Result so far: 8.0
Subtracting 616 from 639 leaves us with 23.
Take the next digit (9) from the dividend and append it to 23, then repeat: 239 / 77

Moving on to step 4:
If we divide 239 by 77, we get 3 and a remainder of 8.
The number 3 becomes the next digit in our result. 
Result so far: 83.0
Subtracting 231 from 239 leaves us with 8.
Include the next digit (6) from the dividend after 8, then repeat: 86 / 77

On to step 5:
The number 77 fits into 86 1 times, leaving a remainder of 9.
The next digit of our result is 1. 
Result so far: 831.0
The remainder is 9 after subtracting 77 from 86.
Include the next digit (6) from the dividend after 9, then repeat: 96 / 77

Advancing to step 6:
96 divided by 77 is 1 with a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 8311.0
Subtracting 77 from 96 leaves us with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 7:
If we divide 190 by 77, we get 2 and a remainder of 36.
Record the quotient 2 as the next digit in the result. 
Result so far: 8311.2
The remainder is 36 after subtracting 154 from 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Step 8:
If we divide 360 by 77, we get 4 and a remainder of 52.
The number 4 becomes the next digit in our result. 
Result so far: 8311.24
If we take 308 away from 360, we end up with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Step 9:
77 goes into 520 6 times with a remainder of 58.
Record the quotient 6 as the next digit in the result. 
Result so far: 8311.246
The remainder is 58 after subtracting 462 from 520.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

On to step 10:
The number 77 fits into 580 7 times, leaving a remainder of 41.
The number 7 becomes the next digit in our result. 
Result so far: 8311.2467
The remainder is 41 after subtracting 539 from 580.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

Step 11:
The number 77 fits into 410 5 times, leaving a remainder of 25.
Put 5 as the next digit of the answer. 
Result so far: 8311.24675
If we subtract 385 from 410, we get 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Moving on to step 12:
250 divided by 77 is 3 with a remainder of 19.
The next digit of our result is 3. 
Result so far: 8311.246753
Subtracting 231 from 250 leaves us with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 13:
When dividing 190 by 77, we get 2 with a remainder of 36.
The number 2 becomes the next digit in our result. 
Result so far: 8311.2467532
Subtract 154 from 190 to get 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Advancing to step 14:
The number 77 fits into 360 4 times, leaving a remainder of 52.
The number 4 becomes the next digit in our result. 
Result so far: 8311.24675324
If we take 308 away from 360, we end up with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

After the division, we end up with 8311.24675324 and a remainder of 5.2e-08.