43392991 divided by 90 
The aim is to understand the frequency of 90 in 43392991.

Going ahead to step 1:
If we divide 4 by 90, we get 0 and a remainder of 4.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Fetch the next digit (3) from the dividend, attach it to 4 and continue: 43 / 90

Advancing to step 2:
When dividing 43 by 90, we get 0 with a remainder of 43.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 43 after subtracting 0 from 43.
Fetch the next digit (3) from the dividend, attach it to 43 and continue: 433 / 90

On to step 3:
433 divided by 90 is 4 with a remainder of 73.
The next digit of our result is 4. 
Result so far: 4.0
If we take 360 away from 433, we end up with 73.
Bring next digit (9) of the dividend behind the 73 and repeat the process: 739 / 90

Advancing to step 4:
90 goes into 739 8 times with a remainder of 19.
Write down 8 as next digit of the result. 
Result so far: 48.0
Deduct 720 from 739 and we're left with 19.
Bring next digit (2) of the dividend behind the 19 and repeat the process: 192 / 90

Step 5:
90 can be fit into 192 2 times, resulting in a remainder of 12.
Record the quotient 2 as the next digit in the result. 
Result so far: 482.0
Subtract 180 from 192 to get 12.
Bring next digit (9) of the dividend behind the 12 and repeat the process: 129 / 90

Advancing to step 6:
The number 90 fits into 129 1 times, leaving a remainder of 39.
The number 1 becomes the next digit in our result. 
Result so far: 4821.0
The remainder is 39 after subtracting 90 from 129.
Fetch the next digit (9) from the dividend, attach it to 39 and continue: 399 / 90

Step 7:
The number 90 fits into 399 4 times, leaving a remainder of 39.
Write down 4 as next digit of the result. 
Result so far: 48214.0
If we take 360 away from 399, we end up with 39.
Take the next digit (1) from the dividend and append it to 39, then repeat: 391 / 90

Moving on to step 8:
When dividing 391 by 90, we get 4 with a remainder of 31.
Write down 4 as next digit of the result. 
Result so far: 482144.0
If we take 360 away from 391, we end up with 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Step 9:
90 can be fit into 310 3 times, resulting in a remainder of 40.
Put 3 as the next digit of the answer. 
Result so far: 482144.3
Subtracting 270 from 310 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 10:
The number 90 fits into 400 4 times, leaving a remainder of 40.
Write down 4 as next digit of the result. 
Result so far: 482144.34
Subtracting 360 from 400 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 11:
90 goes into 400 4 times with a remainder of 40.
Write down 4 as next digit of the result. 
Result so far: 482144.344
The remainder is 40 after subtracting 360 from 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

In conclusion, the division gives 482144.344 with a balance of 0.004.