639594 ÷ 77 
We want to figure out the number of times 639594 can be divided by 77.

Step 1:
When dividing 6 by 77, we get 0 with a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Include the next digit (3) from the dividend after 6, then repeat: 63 / 77

Step 2:
When dividing 63 by 77, we get 0 with a remainder of 63.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 63 to get 63.
Grab the next digit (9) from the dividend, add it to 63, then carry on: 639 / 77

On to step 3:
When dividing 639 by 77, we get 8 with a remainder of 23.
Use 8 as the next digit of our solution. 
Result so far: 8.0
Deduct 616 from 639 and we're left with 23.
Grab the next digit (5) from the dividend, add it to 23, then carry on: 235 / 77

Moving on to step 4:
235 divided by 77 is 3 with a remainder of 4.
The number 3 becomes the next digit in our result. 
Result so far: 83.0
Deduct 231 from 235 and we're left with 4.
Include the next digit (9) from the dividend after 4, then repeat: 49 / 77

Let's proceed to step 5:
49 divided by 77 is 0 with a remainder of 49.
Write down 0 as next digit of the result. 
Result so far: 830.0
The remainder is 49 after subtracting 0 from 49.
Bring next digit (4) of the dividend behind the 49 and repeat the process: 494 / 77

Step 6:
494 divided by 77 is 6 with a remainder of 32.
The number 6 becomes the next digit in our result. 
Result so far: 8306.0
If we subtract 462 from 494, we get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Let's proceed to step 7:
77 can be fit into 320 4 times, resulting in a remainder of 12.
Record the quotient 4 as the next digit in the result. 
Result so far: 8306.4
Deduct 308 from 320 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 8:
120 divided by 77 is 1 with a remainder of 43.
Use 1 as the next digit of our solution. 
Result so far: 8306.41
Subtracting 77 from 120 leaves us with 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

Going ahead to step 9:
77 can be fit into 430 5 times, resulting in a remainder of 45.
Use 5 as the next digit of our solution. 
Result so far: 8306.415
If we subtract 385 from 430, we get 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Advancing to step 10:
The number 77 fits into 450 5 times, leaving a remainder of 65.
The number 5 becomes the next digit in our result. 
Result so far: 8306.4155
If we subtract 385 from 450, we get 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

After the division, we end up with 8306.4155 and a remainder of 0.00065.