80937541 divided by 643 
The aim is to understand the frequency of 643 in 80937541.

Moving on to step 1:
643 can be fit into 8 0 times, resulting in a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Fetch the next digit (0) from the dividend, attach it to 8 and continue: 80 / 643

Advancing to step 2:
643 goes into 80 0 times with a remainder of 80.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 80, we get 80.
Grab the next digit (9) from the dividend, add it to 80, then carry on: 809 / 643

On to step 3:
When dividing 809 by 643, we get 1 with a remainder of 166.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtract 643 from 809 to get 166.
Take the next digit (3) from the dividend and append it to 166, then repeat: 1663 / 643

Step 4:
When dividing 1663 by 643, we get 2 with a remainder of 377.
Write down 2 as next digit of the result. 
Result so far: 12.0
Deduct 1286 from 1663 and we're left with 377.
Bring next digit (7) of the dividend behind the 377 and repeat the process: 3777 / 643

Moving on to step 5:
When dividing 3777 by 643, we get 5 with a remainder of 562.
Write down 5 as next digit of the result. 
Result so far: 125.0
Subtract 3215 from 3777 to get 562.
Bring next digit (5) of the dividend behind the 562 and repeat the process: 5625 / 643

Step 6:
643 goes into 5625 8 times with a remainder of 481.
The number 8 becomes the next digit in our result. 
Result so far: 1258.0
If we take 5144 away from 5625, we end up with 481.
Bring next digit (4) of the dividend behind the 481 and repeat the process: 4814 / 643

Advancing to step 7:
The number 643 fits into 4814 7 times, leaving a remainder of 313.
The number 7 becomes the next digit in our result. 
Result so far: 12587.0
Subtracting 4501 from 4814 leaves us with 313.
Grab the next digit (1) from the dividend, add it to 313, then carry on: 3131 / 643

Moving on to step 8:
643 goes into 3131 4 times with a remainder of 559.
Record the quotient 4 as the next digit in the result. 
Result so far: 125874.0
Deduct 2572 from 3131 and we're left with 559.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5590, and continue the process.

Advancing to step 9:
643 goes into 5590 8 times with a remainder of 446.
Put 8 as the next digit of the answer. 
Result so far: 125874.8
If we take 5144 away from 5590, we end up with 446.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4460, and continue the process.

Step 10:
4460 divided by 643 is 6 with a remainder of 602.
Write down 6 as next digit of the result. 
Result so far: 125874.86
The remainder is 602 after subtracting 3858 from 4460.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6020, and continue the process.

Advancing to step 11:
643 goes into 6020 9 times with a remainder of 233.
Put 9 as the next digit of the answer. 
Result so far: 125874.869
Subtracting 5787 from 6020 leaves us with 233.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2330, and continue the process.

Moving on to step 12:
If we divide 2330 by 643, we get 3 and a remainder of 401.
Use 3 as the next digit of our solution. 
Result so far: 125874.8693
If we take 1929 away from 2330, we end up with 401.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4010, and continue the process.

On to step 13:
643 can be fit into 4010 6 times, resulting in a remainder of 152.
Record the quotient 6 as the next digit in the result. 
Result so far: 125874.86936
If we subtract 3858 from 4010, we get 152.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1520, and continue the process.

Step 14:
If we divide 1520 by 643, we get 2 and a remainder of 234.
Use 2 as the next digit of our solution. 
Result so far: 125874.869362
Deduct 1286 from 1520 and we're left with 234.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2340, and continue the process.

Advancing to step 15:
643 can be fit into 2340 3 times, resulting in a remainder of 411.
Put 3 as the next digit of the answer. 
Result so far: 125874.8693623
Subtracting 1929 from 2340 leaves us with 411.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4110, and continue the process.

Let's proceed to step 16:
When dividing 4110 by 643, we get 6 with a remainder of 252.
Write down 6 as next digit of the result. 
Result so far: 125874.86936236
The remainder is 252 after subtracting 3858 from 4110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2520, and continue the process.

After the division, we end up with 125874.86936236 and a remainder of 2.52e-07.