We look at the division of 517740 by 28 
The aim is to understand the frequency of 28 in 517740.

Step 1:
5 divided by 28 is 0 with a remainder of 5.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 28

On to step 2:
51 divided by 28 is 1 with a remainder of 23.
The next digit of our result is 1. 
Result so far: 1.0
If we subtract 28 from 51, we get 23.
Append the next digit (7) from the dividend to 23 and continue with: 237 / 28

Moving on to step 3:
If we divide 237 by 28, we get 8 and a remainder of 13.
Use 8 as the next digit of our solution. 
Result so far: 18.0
The remainder is 13 after subtracting 224 from 237.
Take the next digit (7) from the dividend and append it to 13, then repeat: 137 / 28

Moving on to step 4:
28 can be fit into 137 4 times, resulting in a remainder of 25.
Put 4 as the next digit of the answer. 
Result so far: 184.0
Deduct 112 from 137 and we're left with 25.
Grab the next digit (4) from the dividend, add it to 25, then carry on: 254 / 28

Going ahead to step 5:
The number 28 fits into 254 9 times, leaving a remainder of 2.
Put 9 as the next digit of the answer. 
Result so far: 1849.0
Subtract 252 from 254 to get 2.
Append the next digit (0) from the dividend to 2 and continue with: 20 / 28

On to step 6:
28 can be fit into 20 0 times, resulting in a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 18490.0
If we take 0 away from 20, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 7:
28 goes into 200 7 times with a remainder of 4.
Record the quotient 7 as the next digit in the result. 
Result so far: 18490.7
Subtract 196 from 200 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 8:
If we divide 40 by 28, we get 1 and a remainder of 12.
Write down 1 as next digit of the result. 
Result so far: 18490.71
Deduct 28 from 40 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 9:
The number 28 fits into 120 4 times, leaving a remainder of 8.
The number 4 becomes the next digit in our result. 
Result so far: 18490.714
Deduct 112 from 120 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 10:
When dividing 80 by 28, we get 2 with a remainder of 24.
Write down 2 as next digit of the result. 
Result so far: 18490.7142
The remainder is 24 after subtracting 56 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Let's proceed to step 11:
The number 28 fits into 240 8 times, leaving a remainder of 16.
The number 8 becomes the next digit in our result. 
Result so far: 18490.71428
If we take 224 away from 240, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Moving on to step 12:
160 divided by 28 is 5 with a remainder of 20.
The next digit of our result is 5. 
Result so far: 18490.714285
Subtracting 140 from 160 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 13:
The number 28 fits into 200 7 times, leaving a remainder of 4.
The number 7 becomes the next digit in our result. 
Result so far: 18490.7142857
If we take 196 away from 200, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 14:
28 can be fit into 40 1 times, resulting in a remainder of 12.
The next digit of our result is 1. 
Result so far: 18490.71428571
Subtracting 28 from 40 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

After the division, we end up with 18490.71428571 and a remainder of 1.2e-08.