We divide 542941 by 81
The aim is to understand the frequency of 81 in 542941.

Advancing to step 1:
If we divide 5 by 81, we get 0 and a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 5, we end up with 5.
Bring next digit (4) of the dividend behind the 5 and repeat the process: 54 / 81

Let's proceed to step 2:
When dividing 54 by 81, we get 0 with a remainder of 54.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 54, we end up with 54.
Take the next digit (2) from the dividend and append it to 54, then repeat: 542 / 81

Going ahead to step 3:
If we divide 542 by 81, we get 6 and a remainder of 56.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
If we take 486 away from 542, we end up with 56.
Fetch the next digit (9) from the dividend, attach it to 56 and continue: 569 / 81

On to step 4:
569 divided by 81 is 7 with a remainder of 2.
Record the quotient 7 as the next digit in the result. 
Result so far: 67.0
The remainder is 2 after subtracting 567 from 569.
Include the next digit (4) from the dividend after 2, then repeat: 24 / 81

On to step 5:
If we divide 24 by 81, we get 0 and a remainder of 24.
The next digit of our result is 0. 
Result so far: 670.0
If we subtract 0 from 24, we get 24.
Take the next digit (1) from the dividend and append it to 24, then repeat: 241 / 81

Step 6:
81 goes into 241 2 times with a remainder of 79.
Record the quotient 2 as the next digit in the result. 
Result so far: 6702.0
Subtract 162 from 241 to get 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

Step 7:
If we divide 790 by 81, we get 9 and a remainder of 61.
The next digit of our result is 9. 
Result so far: 6702.9
If we take 729 away from 790, we end up with 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

On to step 8:
If we divide 610 by 81, we get 7 and a remainder of 43.
Use 7 as the next digit of our solution. 
Result so far: 6702.97
If we subtract 567 from 610, we get 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

Going ahead to step 9:
When dividing 430 by 81, we get 5 with a remainder of 25.
The number 5 becomes the next digit in our result. 
Result so far: 6702.975
Subtracting 405 from 430 leaves us with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Advancing to step 10:
When dividing 250 by 81, we get 3 with a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 6702.9753
If we take 243 away from 250, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Let's proceed to step 11:
81 can be fit into 70 0 times, resulting in a remainder of 70.
Put 0 as the next digit of the answer. 
Result so far: 6702.9753
The remainder is 70 after subtracting 0 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Step 12:
The number 81 fits into 700 8 times, leaving a remainder of 52.
The next digit of our result is 8. 
Result so far: 6702.975308
Subtract 648 from 700 to get 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Moving on to step 13:
The number 81 fits into 520 6 times, leaving a remainder of 34.
The next digit of our result is 6. 
Result so far: 6702.9753086
If we take 486 away from 520, we end up with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Moving on to step 14:
If we divide 340 by 81, we get 4 and a remainder of 16.
Use 4 as the next digit of our solution. 
Result so far: 6702.97530864
Subtracting 324 from 340 leaves us with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

The final outcome is 6702.97530864, with a leftover of 1.6e-08.