90219850 ÷ 403 
The aim is to understand the frequency of 403 in 90219850.

Step 1:
If we divide 9 by 403, we get 0 and a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 9 after subtracting 0 from 9.
Bring next digit (0) of the dividend behind the 9 and repeat the process: 90 / 403

Moving on to step 2:
When dividing 90 by 403, we get 0 with a remainder of 90.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 90 and we're left with 90.
Grab the next digit (2) from the dividend, add it to 90, then carry on: 902 / 403

Going ahead to step 3:
When dividing 902 by 403, we get 2 with a remainder of 96.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
If we take 806 away from 902, we end up with 96.
Include the next digit (1) from the dividend after 96, then repeat: 961 / 403

Going ahead to step 4:
403 can be fit into 961 2 times, resulting in a remainder of 155.
Use 2 as the next digit of our solution. 
Result so far: 22.0
Subtracting 806 from 961 leaves us with 155.
Append the next digit (9) from the dividend to 155 and continue with: 1559 / 403

On to step 5:
When dividing 1559 by 403, we get 3 with a remainder of 350.
The number 3 becomes the next digit in our result. 
Result so far: 223.0
If we take 1209 away from 1559, we end up with 350.
Append the next digit (8) from the dividend to 350 and continue with: 3508 / 403

Step 6:
If we divide 3508 by 403, we get 8 and a remainder of 284.
Write down 8 as next digit of the result. 
Result so far: 2238.0
If we take 3224 away from 3508, we end up with 284.
Bring next digit (5) of the dividend behind the 284 and repeat the process: 2845 / 403

On to step 7:
When dividing 2845 by 403, we get 7 with a remainder of 24.
Put 7 as the next digit of the answer. 
Result so far: 22387.0
Subtracting 2821 from 2845 leaves us with 24.
Include the next digit (0) from the dividend after 24, then repeat: 240 / 403

Going ahead to step 8:
The number 403 fits into 240 0 times, leaving a remainder of 240.
The number 0 becomes the next digit in our result. 
Result so far: 223870.0
The remainder is 240 after subtracting 0 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Let's proceed to step 9:
403 can be fit into 2400 5 times, resulting in a remainder of 385.
Use 5 as the next digit of our solution. 
Result so far: 223870.5
Deduct 2015 from 2400 and we're left with 385.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3850, and continue the process.

Let's proceed to step 10:
When dividing 3850 by 403, we get 9 with a remainder of 223.
The next digit of our result is 9. 
Result so far: 223870.59
Subtract 3627 from 3850 to get 223.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2230, and continue the process.

Moving on to step 11:
403 can be fit into 2230 5 times, resulting in a remainder of 215.
Record the quotient 5 as the next digit in the result. 
Result so far: 223870.595
Subtracting 2015 from 2230 leaves us with 215.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2150, and continue the process.

Step 12:
If we divide 2150 by 403, we get 5 and a remainder of 135.
The next digit of our result is 5. 
Result so far: 223870.5955
Subtracting 2015 from 2150 leaves us with 135.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1350, and continue the process.

The final outcome is 223870.5955, with a leftover of 0.00135.