We look at the division of 43663239 by 900 
The aim is to understand the frequency of 900 in 43663239.

On to step 1:
900 goes into 4 0 times with a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Include the next digit (3) from the dividend after 4, then repeat: 43 / 900

Going ahead to step 2:
43 divided by 900 is 0 with a remainder of 43.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 43, we end up with 43.
Include the next digit (6) from the dividend after 43, then repeat: 436 / 900

Going ahead to step 3:
436 divided by 900 is 0 with a remainder of 436.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 436, we get 436.
Take the next digit (6) from the dividend and append it to 436, then repeat: 4366 / 900

Going ahead to step 4:
4366 divided by 900 is 4 with a remainder of 766.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
If we subtract 3600 from 4366, we get 766.
Append the next digit (3) from the dividend to 766 and continue with: 7663 / 900

Step 5:
7663 divided by 900 is 8 with a remainder of 463.
Record the quotient 8 as the next digit in the result. 
Result so far: 48.0
If we subtract 7200 from 7663, we get 463.
Bring next digit (2) of the dividend behind the 463 and repeat the process: 4632 / 900

Moving on to step 6:
4632 divided by 900 is 5 with a remainder of 132.
Write down 5 as next digit of the result. 
Result so far: 485.0
Deduct 4500 from 4632 and we're left with 132.
Grab the next digit (3) from the dividend, add it to 132, then carry on: 1323 / 900

Going ahead to step 7:
When dividing 1323 by 900, we get 1 with a remainder of 423.
The number 1 becomes the next digit in our result. 
Result so far: 4851.0
If we subtract 900 from 1323, we get 423.
Bring next digit (9) of the dividend behind the 423 and repeat the process: 4239 / 900

Advancing to step 8:
When dividing 4239 by 900, we get 4 with a remainder of 639.
The number 4 becomes the next digit in our result. 
Result so far: 48514.0
The remainder is 639 after subtracting 3600 from 4239.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6390, and continue the process.

Moving on to step 9:
900 goes into 6390 7 times with a remainder of 90.
The number 7 becomes the next digit in our result. 
Result so far: 48514.7
Subtract 6300 from 6390 to get 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

Let's proceed to step 10:
900 divided by 900 is 1 with a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 48514.71
The remainder is 0 after subtracting 900 from 900.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 11:
900 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 48514.71
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 12:
0 divided by 900 is 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 48514.71
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 48514.71, with a leftover of 0.0.