We look at the division of 21016143 by 505 
The aim is to understand the frequency of 505 in 21016143.

Advancing to step 1:
When dividing 2 by 505, we get 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 505

Moving on to step 2:
21 divided by 505 is 0 with a remainder of 21.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 21 and we're left with 21.
Bring next digit (0) of the dividend behind the 21 and repeat the process: 210 / 505

Moving on to step 3:
When dividing 210 by 505, we get 0 with a remainder of 210.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 210 to get 210.
Bring next digit (1) of the dividend behind the 210 and repeat the process: 2101 / 505

On to step 4:
505 goes into 2101 4 times with a remainder of 81.
The next digit of our result is 4. 
Result so far: 4.0
If we take 2020 away from 2101, we end up with 81.
Include the next digit (6) from the dividend after 81, then repeat: 816 / 505

Moving on to step 5:
505 goes into 816 1 times with a remainder of 311.
The number 1 becomes the next digit in our result. 
Result so far: 41.0
The remainder is 311 after subtracting 505 from 816.
Include the next digit (1) from the dividend after 311, then repeat: 3111 / 505

Step 6:
505 can be fit into 3111 6 times, resulting in a remainder of 81.
Record the quotient 6 as the next digit in the result. 
Result so far: 416.0
Subtract 3030 from 3111 to get 81.
Bring next digit (4) of the dividend behind the 81 and repeat the process: 814 / 505

On to step 7:
When dividing 814 by 505, we get 1 with a remainder of 309.
The number 1 becomes the next digit in our result. 
Result so far: 4161.0
If we take 505 away from 814, we end up with 309.
Append the next digit (3) from the dividend to 309 and continue with: 3093 / 505

Going ahead to step 8:
The number 505 fits into 3093 6 times, leaving a remainder of 63.
Use 6 as the next digit of our solution. 
Result so far: 41616.0
The remainder is 63 after subtracting 3030 from 3093.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Step 9:
630 divided by 505 is 1 with a remainder of 125.
Write down 1 as next digit of the result. 
Result so far: 41616.1
Subtracting 505 from 630 leaves us with 125.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1250, and continue the process.

Advancing to step 10:
If we divide 1250 by 505, we get 2 and a remainder of 240.
Write down 2 as next digit of the result. 
Result so far: 41616.12
Subtract 1010 from 1250 to get 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 11:
The number 505 fits into 2400 4 times, leaving a remainder of 380.
Put 4 as the next digit of the answer. 
Result so far: 41616.124
Subtracting 2020 from 2400 leaves us with 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3800, and continue the process.

Going ahead to step 12:
505 goes into 3800 7 times with a remainder of 265.
Put 7 as the next digit of the answer. 
Result so far: 41616.1247
If we subtract 3535 from 3800, we get 265.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

Moving on to step 13:
If we divide 2650 by 505, we get 5 and a remainder of 125.
Use 5 as the next digit of our solution. 
Result so far: 41616.12475
Subtract 2525 from 2650 to get 125.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1250, and continue the process.

Moving on to step 14:
1250 divided by 505 is 2 with a remainder of 240.
Record the quotient 2 as the next digit in the result. 
Result so far: 41616.124752
Subtract 1010 from 1250 to get 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

Advancing to step 15:
505 goes into 2400 4 times with a remainder of 380.
The number 4 becomes the next digit in our result. 
Result so far: 41616.1247524
If we subtract 2020 from 2400, we get 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3800, and continue the process.

Going ahead to step 16:
If we divide 3800 by 505, we get 7 and a remainder of 265.
The number 7 becomes the next digit in our result. 
Result so far: 41616.12475247
If we subtract 3535 from 3800, we get 265.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

After the division, we end up with 41616.12475247 and a remainder of 2.65e-07.