Let's divide 870228 by 81
The aim is to understand the frequency of 81 in 870228.

Moving on to step 1:
When dividing 8 by 81, we get 0 with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Take the next digit (7) from the dividend and append it to 8, then repeat: 87 / 81

Going ahead to step 2:
81 goes into 87 1 times with a remainder of 6.
Put 1 as the next digit of the answer. 
Result so far: 1.0
The remainder is 6 after subtracting 81 from 87.
Bring next digit (0) of the dividend behind the 6 and repeat the process: 60 / 81

Moving on to step 3:
The number 81 fits into 60 0 times, leaving a remainder of 60.
The number 0 becomes the next digit in our result. 
Result so far: 10.0
Subtract 0 from 60 to get 60.
Append the next digit (2) from the dividend to 60 and continue with: 602 / 81

Step 4:
602 divided by 81 is 7 with a remainder of 35.
Put 7 as the next digit of the answer. 
Result so far: 107.0
If we take 567 away from 602, we end up with 35.
Fetch the next digit (2) from the dividend, attach it to 35 and continue: 352 / 81

Let's proceed to step 5:
If we divide 352 by 81, we get 4 and a remainder of 28.
Write down 4 as next digit of the result. 
Result so far: 1074.0
Subtract 324 from 352 to get 28.
Append the next digit (8) from the dividend to 28 and continue with: 288 / 81

Let's proceed to step 6:
The number 81 fits into 288 3 times, leaving a remainder of 45.
Put 3 as the next digit of the answer. 
Result so far: 10743.0
Subtracting 243 from 288 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.

Advancing to step 7:
The number 81 fits into 450 5 times, leaving a remainder of 45.
The number 5 becomes the next digit in our result. 
Result so far: 10743.5
Subtract 405 from 450 to get 45.
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:
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: 10743.55
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 quotient of the division is 10743.55, and the remainder is 0.045.