124398 divided by 81 
The aim is to understand the frequency of 81 in 124398.

Step 1:
When dividing 1 by 81, we get 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 81

Advancing to step 2:
12 divided by 81 is 0 with a remainder of 12.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 12, we end up with 12.
Fetch the next digit (4) from the dividend, attach it to 12 and continue: 124 / 81

On to step 3:
124 divided by 81 is 1 with a remainder of 43.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 81 from 124 and we're left with 43.
Append the next digit (3) from the dividend to 43 and continue with: 433 / 81

Advancing to step 4:
If we divide 433 by 81, we get 5 and a remainder of 28.
Use 5 as the next digit of our solution. 
Result so far: 15.0
Deduct 405 from 433 and we're left with 28.
Append the next digit (9) from the dividend to 28 and continue with: 289 / 81

Advancing to step 5:
If we divide 289 by 81, we get 3 and a remainder of 46.
Use 3 as the next digit of our solution. 
Result so far: 153.0
The remainder is 46 after subtracting 243 from 289.
Grab the next digit (8) from the dividend, add it to 46, then carry on: 468 / 81

Moving on to step 6:
468 divided by 81 is 5 with a remainder of 63.
Write down 5 as next digit of the result. 
Result so far: 1535.0
Subtracting 405 from 468 leaves us with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

On to step 7:
81 can be fit into 630 7 times, resulting in a remainder of 63.
Write down 7 as next digit of the result. 
Result so far: 1535.7
If we take 567 away from 630, we end up with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Moving on to step 8:
630 divided by 81 is 7 with a remainder of 63.
Record the quotient 7 as the next digit in the result. 
Result so far: 1535.77
Subtracting 567 from 630 leaves us with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

The quotient of the division is 1535.77, and the remainder is 0.063.