169490 divided by 81 
The aim is to understand the frequency of 81 in 169490.

Advancing to step 1:
If we divide 1 by 81, we get 0 and a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Include the next digit (6) from the dividend after 1, then repeat: 16 / 81

On to step 2:
If we divide 16 by 81, we get 0 and a remainder of 16.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 16 and we're left with 16.
Fetch the next digit (9) from the dividend, attach it to 16 and continue: 169 / 81

Moving on to step 3:
When dividing 169 by 81, we get 2 with a remainder of 7.
Write down 2 as next digit of the result. 
Result so far: 2.0
Subtract 162 from 169 to get 7.
Append the next digit (4) from the dividend to 7 and continue with: 74 / 81

Going ahead to step 4:
74 divided by 81 is 0 with a remainder of 74.
The next digit of our result is 0. 
Result so far: 20.0
If we subtract 0 from 74, we get 74.
Bring next digit (9) of the dividend behind the 74 and repeat the process: 749 / 81

Advancing to step 5:
When dividing 749 by 81, we get 9 with a remainder of 20.
Use 9 as the next digit of our solution. 
Result so far: 209.0
If we subtract 729 from 749, we get 20.
Fetch the next digit (0) from the dividend, attach it to 20 and continue: 200 / 81

Moving on to step 6:
81 can be fit into 200 2 times, resulting in a remainder of 38.
Use 2 as the next digit of our solution. 
Result so far: 2092.0
The remainder is 38 after subtracting 162 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

On to step 7:
81 goes into 380 4 times with a remainder of 56.
The number 4 becomes the next digit in our result. 
Result so far: 2092.4
If we take 324 away from 380, we end up with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Going ahead to step 8:
The number 81 fits into 560 6 times, leaving a remainder of 74.
Record the quotient 6 as the next digit in the result. 
Result so far: 2092.46
The remainder is 74 after subtracting 486 from 560.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Step 9:
When dividing 740 by 81, we get 9 with a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 2092.469
The remainder is 11 after subtracting 729 from 740.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 10:
If we divide 110 by 81, we get 1 and a remainder of 29.
The next digit of our result is 1. 
Result so far: 2092.4691
Subtract 81 from 110 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Step 11:
290 divided by 81 is 3 with a remainder of 47.
Put 3 as the next digit of the answer. 
Result so far: 2092.46913
If we take 243 away from 290, we end up with 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

On to step 12:
When dividing 470 by 81, we get 5 with a remainder of 65.
The number 5 becomes the next digit in our result. 
Result so far: 2092.469135
If we take 405 away from 470, we end up with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Moving on to step 13:
If we divide 650 by 81, we get 8 and a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 2092.4691358
The remainder is 2 after subtracting 648 from 650.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 14:
20 divided by 81 is 0 with a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 2092.4691358
Subtracting 0 from 20 leaves us 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.

After the division, we end up with 2092.4691358 and a remainder of 2e-08.