We're dividing 72138939 by 643 
We're looking to find how many times 643 goes into 72138939.

Advancing to step 1:
The number 643 fits into 7 0 times, leaving a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 7 to get 7.
Include the next digit (2) from the dividend after 7, then repeat: 72 / 643

Step 2:
The number 643 fits into 72 0 times, leaving a remainder of 72.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 72 to get 72.
Fetch the next digit (1) from the dividend, attach it to 72 and continue: 721 / 643

Moving on to step 3:
If we divide 721 by 643, we get 1 and a remainder of 78.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 78 after subtracting 643 from 721.
Take the next digit (3) from the dividend and append it to 78, then repeat: 783 / 643

Advancing to step 4:
783 divided by 643 is 1 with a remainder of 140.
The next digit of our result is 1. 
Result so far: 11.0
The remainder is 140 after subtracting 643 from 783.
Fetch the next digit (8) from the dividend, attach it to 140 and continue: 1408 / 643

Advancing to step 5:
When dividing 1408 by 643, we get 2 with a remainder of 122.
Record the quotient 2 as the next digit in the result. 
Result so far: 112.0
Subtracting 1286 from 1408 leaves us with 122.
Bring next digit (9) of the dividend behind the 122 and repeat the process: 1229 / 643

Advancing to step 6:
When dividing 1229 by 643, we get 1 with a remainder of 586.
Use 1 as the next digit of our solution. 
Result so far: 1121.0
The remainder is 586 after subtracting 643 from 1229.
Take the next digit (3) from the dividend and append it to 586, then repeat: 5863 / 643

Let's proceed to step 7:
643 can be fit into 5863 9 times, resulting in a remainder of 76.
The next digit of our result is 9. 
Result so far: 11219.0
Deduct 5787 from 5863 and we're left with 76.
Fetch the next digit (9) from the dividend, attach it to 76 and continue: 769 / 643

Let's proceed to step 8:
If we divide 769 by 643, we get 1 and a remainder of 126.
Record the quotient 1 as the next digit in the result. 
Result so far: 112191.0
Subtract 643 from 769 to get 126.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1260, and continue the process.

Going ahead to step 9:
643 can be fit into 1260 1 times, resulting in a remainder of 617.
The number 1 becomes the next digit in our result. 
Result so far: 112191.1
If we subtract 643 from 1260, we get 617.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6170, and continue the process.

Step 10:
When dividing 6170 by 643, we get 9 with a remainder of 383.
Write down 9 as next digit of the result. 
Result so far: 112191.19
If we subtract 5787 from 6170, we get 383.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3830, and continue the process.

Let's proceed to step 11:
643 can be fit into 3830 5 times, resulting in a remainder of 615.
Record the quotient 5 as the next digit in the result. 
Result so far: 112191.195
Deduct 3215 from 3830 and we're left with 615.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6150, and continue the process.

Advancing to step 12:
643 can be fit into 6150 9 times, resulting in a remainder of 363.
Write down 9 as next digit of the result. 
Result so far: 112191.1959
The remainder is 363 after subtracting 5787 from 6150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3630, and continue the process.

Let's proceed to step 13:
643 can be fit into 3630 5 times, resulting in a remainder of 415.
Put 5 as the next digit of the answer. 
Result so far: 112191.19595
Deduct 3215 from 3630 and we're left with 415.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4150, and continue the process.

Let's proceed to step 14:
4150 divided by 643 is 6 with a remainder of 292.
Use 6 as the next digit of our solution. 
Result so far: 112191.195956
If we take 3858 away from 4150, we end up with 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

Moving on to step 15:
If we divide 2920 by 643, we get 4 and a remainder of 348.
Put 4 as the next digit of the answer. 
Result so far: 112191.1959564
Deduct 2572 from 2920 and we're left with 348.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3480, and continue the process.

On to step 16:
3480 divided by 643 is 5 with a remainder of 265.
Write down 5 as next digit of the result. 
Result so far: 112191.19595645
Subtract 3215 from 3480 to get 265.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

The final outcome is 112191.19595645, with a leftover of 2.65e-07.