43621239 divided by 353 
The aim is to understand the frequency of 353 in 43621239.

On to step 1:
353 can be fit into 4 0 times, resulting in a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 4 and we're left with 4.
Grab the next digit (3) from the dividend, add it to 4, then carry on: 43 / 353

Advancing to step 2:
If we divide 43 by 353, we get 0 and a remainder of 43.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 43 leaves us with 43.
Append the next digit (6) from the dividend to 43 and continue with: 436 / 353

Step 3:
436 divided by 353 is 1 with a remainder of 83.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtract 353 from 436 to get 83.
Append the next digit (2) from the dividend to 83 and continue with: 832 / 353

Going ahead to step 4:
832 divided by 353 is 2 with a remainder of 126.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
Deduct 706 from 832 and we're left with 126.
Grab the next digit (1) from the dividend, add it to 126, then carry on: 1261 / 353

Moving on to step 5:
The number 353 fits into 1261 3 times, leaving a remainder of 202.
The next digit of our result is 3. 
Result so far: 123.0
The remainder is 202 after subtracting 1059 from 1261.
Take the next digit (2) from the dividend and append it to 202, then repeat: 2022 / 353

Advancing to step 6:
2022 divided by 353 is 5 with a remainder of 257.
Use 5 as the next digit of our solution. 
Result so far: 1235.0
Deduct 1765 from 2022 and we're left with 257.
Bring next digit (3) of the dividend behind the 257 and repeat the process: 2573 / 353

Moving on to step 7:
2573 divided by 353 is 7 with a remainder of 102.
The number 7 becomes the next digit in our result. 
Result so far: 12357.0
Deduct 2471 from 2573 and we're left with 102.
Fetch the next digit (9) from the dividend, attach it to 102 and continue: 1029 / 353

Going ahead to step 8:
353 can be fit into 1029 2 times, resulting in a remainder of 323.
Record the quotient 2 as the next digit in the result. 
Result so far: 123572.0
Deduct 706 from 1029 and we're left with 323.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3230, and continue the process.

On to step 9:
The number 353 fits into 3230 9 times, leaving a remainder of 53.
The number 9 becomes the next digit in our result. 
Result so far: 123572.9
Subtract 3177 from 3230 to get 53.
Since there are no more digits in the dividend, we add a zero to the remainder making it 530, and continue the process.

On to step 10:
The number 353 fits into 530 1 times, leaving a remainder of 177.
The number 1 becomes the next digit in our result. 
Result so far: 123572.91
If we subtract 353 from 530, we get 177.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1770, and continue the process.

Step 11:
If we divide 1770 by 353, we get 5 and a remainder of 5.
The number 5 becomes the next digit in our result. 
Result so far: 123572.915
If we take 1765 away from 1770, 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 12:
When dividing 50 by 353, we get 0 with a remainder of 50.
The next digit of our result is 0. 
Result so far: 123572.915
Subtract 0 from 50 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Moving on to step 13:
When dividing 500 by 353, we get 1 with a remainder of 147.
Write down 1 as next digit of the result. 
Result so far: 123572.91501
Subtracting 353 from 500 leaves us with 147.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1470, and continue the process.

Step 14:
1470 divided by 353 is 4 with a remainder of 58.
The next digit of our result is 4. 
Result so far: 123572.915014
Subtracting 1412 from 1470 leaves us with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

On to step 15:
353 goes into 580 1 times with a remainder of 227.
The number 1 becomes the next digit in our result. 
Result so far: 123572.9150141
Subtract 353 from 580 to get 227.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2270, and continue the process.

Advancing to step 16:
353 goes into 2270 6 times with a remainder of 152.
Use 6 as the next digit of our solution. 
Result so far: 123572.91501416
If we subtract 2118 from 2270, 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.

After the division, we end up with 123572.91501416 and a remainder of 1.52e-07.