528638 divided by 28 
The aim is to understand the frequency of 28 in 528638.

Let's proceed to step 1:
If we divide 5 by 28, we get 0 and a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Grab the next digit (2) from the dividend, add it to 5, then carry on: 52 / 28

Moving on to step 2:
52 divided by 28 is 1 with a remainder of 24.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtract 28 from 52 to get 24.
Bring next digit (8) of the dividend behind the 24 and repeat the process: 248 / 28

Step 3:
28 goes into 248 8 times with a remainder of 24.
Use 8 as the next digit of our solution. 
Result so far: 18.0
If we subtract 224 from 248, we get 24.
Fetch the next digit (6) from the dividend, attach it to 24 and continue: 246 / 28

Going ahead to step 4:
28 can be fit into 246 8 times, resulting in a remainder of 22.
Record the quotient 8 as the next digit in the result. 
Result so far: 188.0
The remainder is 22 after subtracting 224 from 246.
Fetch the next digit (3) from the dividend, attach it to 22 and continue: 223 / 28

Step 5:
28 can be fit into 223 7 times, resulting in a remainder of 27.
The number 7 becomes the next digit in our result. 
Result so far: 1887.0
If we subtract 196 from 223, we get 27.
Append the next digit (8) from the dividend to 27 and continue with: 278 / 28

Moving on to step 6:
28 can be fit into 278 9 times, resulting in a remainder of 26.
The number 9 becomes the next digit in our result. 
Result so far: 18879.0
Deduct 252 from 278 and we're left with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 7:
260 divided by 28 is 9 with a remainder of 8.
The next digit of our result is 9. 
Result so far: 18879.9
Subtract 252 from 260 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 8:
The number 28 fits into 80 2 times, leaving a remainder of 24.
Write down 2 as next digit of the result. 
Result so far: 18879.92
Deduct 56 from 80 and we're left with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Advancing to step 9:
28 goes into 240 8 times with a remainder of 16.
The number 8 becomes the next digit in our result. 
Result so far: 18879.928
Subtract 224 from 240 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 10:
28 can be fit into 160 5 times, resulting in a remainder of 20.
Use 5 as the next digit of our solution. 
Result so far: 18879.9285
Deduct 140 from 160 and we're left 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.

Moving on to step 11:
28 can be fit into 200 7 times, resulting in a remainder of 4.
Record the quotient 7 as the next digit in the result. 
Result so far: 18879.92857
If we subtract 196 from 200, we 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.

Moving on to step 12:
28 goes into 40 1 times with a remainder of 12.
Record the quotient 1 as the next digit in the result. 
Result so far: 18879.928571
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 13:
28 can be fit into 120 4 times, resulting in a remainder of 8.
Record the quotient 4 as the next digit in the result. 
Result so far: 18879.9285714
If we subtract 112 from 120, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 14:
28 goes into 80 2 times with a remainder of 24.
Put 2 as the next digit of the answer. 
Result so far: 18879.92857142
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.

After the division, we end up with 18879.92857142 and a remainder of 2.4e-08.