612643 divided by 3 
We're looking to find how many times 3 goes into 612643.

Step 1:
6 divided by 3 is 2 with a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Deduct 6 from 6 and we're left with 0.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 3

Moving on to step 2:
If we divide 1 by 3, we get 0 and a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 20.0
Subtracting 0 from 1 leaves us with 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 3

Step 3:
The number 3 fits into 12 4 times, leaving a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 204.0
If we subtract 12 from 12, we get 0.
Take the next digit (6) from the dividend and append it to 0, then repeat: 6 / 3

On to step 4:
The number 3 fits into 6 2 times, leaving a remainder of 0.
The next digit of our result is 2. 
Result so far: 2042.0
The remainder is 0 after subtracting 6 from 6.
Grab the next digit (4) from the dividend, add it to 0, then carry on: 4 / 3

Going ahead to step 5:
When dividing 4 by 3, we get 1 with a remainder of 1.
The next digit of our result is 1. 
Result so far: 20421.0
Subtracting 3 from 4 leaves us with 1.
Fetch the next digit (3) from the dividend, attach it to 1 and continue: 13 / 3

On to step 6:
When dividing 13 by 3, we get 4 with a remainder of 1.
Put 4 as the next digit of the answer. 
Result so far: 204214.0
If we take 12 away from 13, 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.

Moving on to step 7:
10 divided by 3 is 3 with a remainder of 1.
The next digit of our result is 3. 
Result so far: 204214.3
Deduct 9 from 10 and we're left 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 3, we get 3 with a remainder of 1.
Use 3 as the next digit of our solution. 
Result so far: 204214.33
Subtract 9 from 10 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

After the division, we end up with 204214.33 and a remainder of 0.001.