We're dividing 640004 by 51 
We want to figure out the number of times 640004 can be divided by 51.

Advancing to step 1:
If we divide 6 by 51, we get 0 and 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 (4) from the dividend, attach it to 6 and continue: 64 / 51

Let's proceed to step 2:
When dividing 64 by 51, we get 1 with a remainder of 13.
The next digit of our result is 1. 
Result so far: 1.0
If we subtract 51 from 64, we get 13.
Take the next digit (0) from the dividend and append it to 13, then repeat: 130 / 51

Step 3:
51 goes into 130 2 times with a remainder of 28.
Put 2 as the next digit of the answer. 
Result so far: 12.0
Subtract 102 from 130 to get 28.
Bring next digit (0) of the dividend behind the 28 and repeat the process: 280 / 51

Moving on to step 4:
51 can be fit into 280 5 times, resulting in a remainder of 25.
Use 5 as the next digit of our solution. 
Result so far: 125.0
If we subtract 255 from 280, we get 25.
Append the next digit (0) from the dividend to 25 and continue with: 250 / 51

Going ahead to step 5:
The number 51 fits into 250 4 times, leaving a remainder of 46.
Write down 4 as next digit of the result. 
Result so far: 1254.0
Subtracting 204 from 250 leaves us with 46.
Fetch the next digit (4) from the dividend, attach it to 46 and continue: 464 / 51

On to step 6:
51 can be fit into 464 9 times, resulting in a remainder of 5.
The next digit of our result is 9. 
Result so far: 12549.0
Subtract 459 from 464 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 7:
If we divide 50 by 51, we get 0 and a remainder of 50.
Put 0 as the next digit of the answer. 
Result so far: 12549.0
Subtracting 0 from 50 leaves us with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 8:
The number 51 fits into 500 9 times, leaving a remainder of 41.
The number 9 becomes the next digit in our result. 
Result so far: 12549.09
If we take 459 away from 500, we end up with 41.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

Advancing to step 9:
If we divide 410 by 51, we get 8 and a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 12549.098
Subtracting 408 from 410 leaves us with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 10:
The number 51 fits into 20 0 times, leaving a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 12549.098
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 11:
51 goes into 200 3 times with a remainder of 47.
Record the quotient 3 as the next digit in the result. 
Result so far: 12549.09803
Deduct 153 from 200 and we're left with 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Let's proceed to step 12:
If we divide 470 by 51, we get 9 and a remainder of 11.
The next digit of our result is 9. 
Result so far: 12549.098039
Subtract 459 from 470 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 13:
If we divide 110 by 51, we get 2 and a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 12549.0980392
Subtracting 102 from 110 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 14:
The number 51 fits into 80 1 times, leaving a remainder of 29.
Use 1 as the next digit of our solution. 
Result so far: 12549.09803921
Subtracting 51 from 80 leaves us 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 outcome is 12549.09803921, with a leftover of 2.9e-08.