21249 ÷ 8 
The aim is to understand the frequency of 8 in 21249.

Step 1:
When dividing 2 by 8, we get 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Grab the next digit (1) from the dividend, add it to 2, then carry on: 21 / 8

Going ahead to step 2:
If we divide 21 by 8, we get 2 and a remainder of 5.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Subtract 16 from 21 to get 5.
Include the next digit (2) from the dividend after 5, then repeat: 52 / 8

Let's proceed to step 3:
52 divided by 8 is 6 with a remainder of 4.
Record the quotient 6 as the next digit in the result. 
Result so far: 26.0
Subtract 48 from 52 to get 4.
Fetch the next digit (4) from the dividend, attach it to 4 and continue: 44 / 8

On to step 4:
8 can be fit into 44 5 times, resulting in a remainder of 4.
Write down 5 as next digit of the result. 
Result so far: 265.0
Deduct 40 from 44 and we're left with 4.
Include the next digit (9) from the dividend after 4, then repeat: 49 / 8

Advancing to step 5:
If we divide 49 by 8, we get 6 and a remainder of 1.
Write down 6 as next digit of the result. 
Result so far: 2656.0
If we take 48 away from 49, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 6:
10 divided by 8 is 1 with a remainder of 2.
Use 1 as the next digit of our solution. 
Result so far: 2656.1
Subtracting 8 from 10 leaves us with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Advancing to step 7:
8 goes into 20 2 times with a remainder of 4.
The number 2 becomes the next digit in our result. 
Result so far: 2656.12
The remainder is 4 after subtracting 16 from 20.
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 8, we get 5 and a remainder of 0.
The number 5 becomes the next digit in our result. 
Result so far: 2656.125
If we subtract 40 from 40, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 9:
When dividing 0 by 8, we get 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 2656.125
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 10:
8 goes into 0 0 times with a remainder of 0.
The next digit of our result is 0. 
Result so far: 2656.125
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 2656.125 with a remainder of 0.0.