212670 ÷ 81 
The aim is to understand the frequency of 81 in 212670.

Advancing to step 1:
81 can be fit into 2 0 times, resulting in a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Fetch the next digit (1) from the dividend, attach it to 2 and continue: 21 / 81

Advancing to step 2:
The number 81 fits into 21 0 times, leaving a remainder of 21.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 21 to get 21.
Take the next digit (2) from the dividend and append it to 21, then repeat: 212 / 81

Step 3:
81 can be fit into 212 2 times, resulting in a remainder of 50.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtracting 162 from 212 leaves us with 50.
Take the next digit (6) from the dividend and append it to 50, then repeat: 506 / 81

On to step 4:
The number 81 fits into 506 6 times, leaving a remainder of 20.
Record the quotient 6 as the next digit in the result. 
Result so far: 26.0
Subtract 486 from 506 to get 20.
Take the next digit (7) from the dividend and append it to 20, then repeat: 207 / 81

Moving on to step 5:
81 can be fit into 207 2 times, resulting in a remainder of 45.
The number 2 becomes the next digit in our result. 
Result so far: 262.0
Subtract 162 from 207 to get 45.
Include the next digit (0) from the dividend after 45, then repeat: 450 / 81

Step 6:
The number 81 fits into 450 5 times, leaving a remainder of 45.
Record the quotient 5 as the next digit in the result. 
Result so far: 2625.0
Subtracting 405 from 450 leaves us with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

On to step 7:
450 divided by 81 is 5 with a remainder of 45.
The number 5 becomes the next digit in our result. 
Result so far: 2625.5
The remainder is 45 after subtracting 405 from 450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Going ahead to step 8:
If we divide 450 by 81, we get 5 and a remainder of 45.
The next digit of our result is 5. 
Result so far: 2625.55
Deduct 405 from 450 and we're left with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

The final result is 2625.55 with a remainder of 0.045.