We're dividing 22403955 by 521 
The aim is to understand the frequency of 521 in 22403955.

Let's proceed to step 1:
521 can be fit into 2 0 times, resulting in a remainder of 2.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Take the next digit (2) from the dividend and append it to 2, then repeat: 22 / 521

Moving on to step 2:
The number 521 fits into 22 0 times, leaving a remainder of 22.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 22 to get 22.
Include the next digit (4) from the dividend after 22, then repeat: 224 / 521

Let's proceed to step 3:
224 divided by 521 is 0 with a remainder of 224.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 224 after subtracting 0 from 224.
Bring next digit (0) of the dividend behind the 224 and repeat the process: 2240 / 521

Let's proceed to step 4:
When dividing 2240 by 521, we get 4 with a remainder of 156.
Use 4 as the next digit of our solution. 
Result so far: 4.0
If we subtract 2084 from 2240, we get 156.
Bring next digit (3) of the dividend behind the 156 and repeat the process: 1563 / 521

Moving on to step 5:
1563 divided by 521 is 3 with a remainder of 0.
The number 3 becomes the next digit in our result. 
Result so far: 43.0
If we take 1563 away from 1563, we end up with 0.
Include the next digit (9) from the dividend after 0, then repeat: 9 / 521

Going ahead to step 6:
521 can be fit into 9 0 times, resulting in a remainder of 9.
Write down 0 as next digit of the result. 
Result so far: 430.0
Deduct 0 from 9 and we're left with 9.
Include the next digit (5) from the dividend after 9, then repeat: 95 / 521

On to step 7:
95 divided by 521 is 0 with a remainder of 95.
Use 0 as the next digit of our solution. 
Result so far: 4300.0
Deduct 0 from 95 and we're left with 95.
Include the next digit (5) from the dividend after 95, then repeat: 955 / 521

Step 8:
521 can be fit into 955 1 times, resulting in a remainder of 434.
Use 1 as the next digit of our solution. 
Result so far: 43001.0
Subtract 521 from 955 to get 434.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4340, and continue the process.

Moving on to step 9:
521 can be fit into 4340 8 times, resulting in a remainder of 172.
The number 8 becomes the next digit in our result. 
Result so far: 43001.8
If we subtract 4168 from 4340, we get 172.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1720, and continue the process.

Step 10:
The number 521 fits into 1720 3 times, leaving a remainder of 157.
Write down 3 as next digit of the result. 
Result so far: 43001.83
The remainder is 157 after subtracting 1563 from 1720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1570, and continue the process.

Let's proceed to step 11:
1570 divided by 521 is 3 with a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 43001.833
Subtract 1563 from 1570 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

The final outcome is 43001.833, with a leftover of 0.0007.