We're dividing 90631010 by 643 
The aim is to understand the frequency of 643 in 90631010.

Let's proceed to step 1:
643 goes into 9 0 times with a remainder of 9.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Append the next digit (0) from the dividend to 9 and continue with: 90 / 643

Step 2:
When dividing 90 by 643, we get 0 with a remainder of 90.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 90 to get 90.
Append the next digit (6) from the dividend to 90 and continue with: 906 / 643

On to step 3:
643 goes into 906 1 times with a remainder of 263.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtract 643 from 906 to get 263.
Bring next digit (3) of the dividend behind the 263 and repeat the process: 2633 / 643

Moving on to step 4:
2633 divided by 643 is 4 with a remainder of 61.
Record the quotient 4 as the next digit in the result. 
Result so far: 14.0
If we subtract 2572 from 2633, we get 61.
Grab the next digit (1) from the dividend, add it to 61, then carry on: 611 / 643

Let's proceed to step 5:
611 divided by 643 is 0 with a remainder of 611.
Use 0 as the next digit of our solution. 
Result so far: 140.0
If we subtract 0 from 611, we get 611.
Grab the next digit (0) from the dividend, add it to 611, then carry on: 6110 / 643

Step 6:
The number 643 fits into 6110 9 times, leaving a remainder of 323.
Write down 9 as next digit of the result. 
Result so far: 1409.0
Subtracting 5787 from 6110 leaves us with 323.
Fetch the next digit (1) from the dividend, attach it to 323 and continue: 3231 / 643

Step 7:
3231 divided by 643 is 5 with a remainder of 16.
The next digit of our result is 5. 
Result so far: 14095.0
If we subtract 3215 from 3231, we get 16.
Append the next digit (0) from the dividend to 16 and continue with: 160 / 643

Going ahead to step 8:
160 divided by 643 is 0 with a remainder of 160.
Record the quotient 0 as the next digit in the result. 
Result so far: 140950.0
The remainder is 160 after subtracting 0 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

Advancing to step 9:
The number 643 fits into 1600 2 times, leaving a remainder of 314.
The next digit of our result is 2. 
Result so far: 140950.2
The remainder is 314 after subtracting 1286 from 1600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3140, and continue the process.

On to step 10:
3140 divided by 643 is 4 with a remainder of 568.
Put 4 as the next digit of the answer. 
Result so far: 140950.24
If we take 2572 away from 3140, we end up with 568.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5680, and continue the process.

Let's proceed to step 11:
The number 643 fits into 5680 8 times, leaving a remainder of 536.
Write down 8 as next digit of the result. 
Result so far: 140950.248
If we subtract 5144 from 5680, we get 536.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5360, and continue the process.

Step 12:
643 can be fit into 5360 8 times, resulting in a remainder of 216.
Use 8 as the next digit of our solution. 
Result so far: 140950.2488
If we take 5144 away from 5360, we end up with 216.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2160, and continue the process.

Our division results in 140950.2488 with a remaining 0.00216.