Let's divide 639966 by 7
We want to divide 639966 by 7.

Moving on to step 1:
7 can be fit into 6 0 times, resulting in a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Take the next digit (3) from the dividend and append it to 6, then repeat: 63 / 7

On to step 2:
If we divide 63 by 7, we get 9 and a remainder of 0.
Write down 9 as next digit of the result. 
Result so far: 9.0
Subtract 63 from 63 to get 0.
Append the next digit (9) from the dividend to 0 and continue with: 9 / 7

Going ahead to step 3:
When dividing 9 by 7, we get 1 with a remainder of 2.
Put 1 as the next digit of the answer. 
Result so far: 91.0
If we subtract 7 from 9, we get 2.
Append the next digit (9) from the dividend to 2 and continue with: 29 / 7

Advancing to step 4:
29 divided by 7 is 4 with a remainder of 1.
Use 4 as the next digit of our solution. 
Result so far: 914.0
If we subtract 28 from 29, we get 1.
Grab the next digit (6) from the dividend, add it to 1, then carry on: 16 / 7

Moving on to step 5:
The number 7 fits into 16 2 times, leaving a remainder of 2.
Write down 2 as next digit of the result. 
Result so far: 9142.0
Subtracting 14 from 16 leaves us with 2.
Fetch the next digit (6) from the dividend, attach it to 2 and continue: 26 / 7

Step 6:
7 goes into 26 3 times with a remainder of 5.
Record the quotient 3 as the next digit in the result. 
Result so far: 91423.0
The remainder is 5 after subtracting 21 from 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 7:
If we divide 50 by 7, we get 7 and a remainder of 1.
Write down 7 as next digit of the result. 
Result so far: 91423.7
If we take 49 away from 50, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Going ahead to step 8:
When dividing 10 by 7, we get 1 with a remainder of 3.
Put 1 as the next digit of the answer. 
Result so far: 91423.71
Subtract 7 from 10 to get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 9:
When dividing 30 by 7, we get 4 with a remainder of 2.
Use 4 as the next digit of our solution. 
Result so far: 91423.714
If we subtract 28 from 30, we get 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:
7 can be fit into 20 2 times, resulting in a remainder of 6.
The number 2 becomes the next digit in our result. 
Result so far: 91423.7142
Subtracting 14 from 20 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Moving on to step 11:
If we divide 60 by 7, we get 8 and a remainder of 4.
Write down 8 as next digit of the result. 
Result so far: 91423.71428
Subtracting 56 from 60 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 12:
If we divide 40 by 7, we get 5 and a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 91423.714285
If we take 35 away from 40, we end up with 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 13:
7 can be fit into 50 7 times, resulting in a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 91423.7142857
Subtracting 49 from 50 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 14:
7 goes into 10 1 times with a remainder of 3.
Record the quotient 1 as the next digit in the result. 
Result so far: 91423.71428571
Deduct 7 from 10 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Our division results in 91423.71428571 with a remaining 3e-09.