We're dividing 687904 by 54 
The aim is to understand the frequency of 54 in 687904.

On to step 1:
When dividing 6 by 54, we get 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Include the next digit (8) from the dividend after 6, then repeat: 68 / 54

Going ahead to step 2:
When dividing 68 by 54, we get 1 with a remainder of 14.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we subtract 54 from 68, we get 14.
Bring next digit (7) of the dividend behind the 14 and repeat the process: 147 / 54

Moving on to step 3:
If we divide 147 by 54, we get 2 and a remainder of 39.
Write down 2 as next digit of the result. 
Result so far: 12.0
Deduct 108 from 147 and we're left with 39.
Grab the next digit (9) from the dividend, add it to 39, then carry on: 399 / 54

Going ahead to step 4:
54 goes into 399 7 times with a remainder of 21.
Put 7 as the next digit of the answer. 
Result so far: 127.0
If we subtract 378 from 399, we get 21.
Include the next digit (0) from the dividend after 21, then repeat: 210 / 54

On to step 5:
If we divide 210 by 54, we get 3 and a remainder of 48.
Record the quotient 3 as the next digit in the result. 
Result so far: 1273.0
Subtract 162 from 210 to get 48.
Fetch the next digit (4) from the dividend, attach it to 48 and continue: 484 / 54

Moving on to step 6:
When dividing 484 by 54, we get 8 with a remainder of 52.
Write down 8 as next digit of the result. 
Result so far: 12738.0
Subtracting 432 from 484 leaves us with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Step 7:
54 goes into 520 9 times with a remainder of 34.
Put 9 as the next digit of the answer. 
Result so far: 12738.9
The remainder is 34 after subtracting 486 from 520.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Advancing to step 8:
340 divided by 54 is 6 with a remainder of 16.
The next digit of our result is 6. 
Result so far: 12738.96
If we take 324 away from 340, we end up 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.

Let's proceed to step 9:
54 can be fit into 160 2 times, resulting in a remainder of 52.
The next digit of our result is 2. 
Result so far: 12738.962
If we take 108 away from 160, we end up with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

On to step 10:
54 goes into 520 9 times with a remainder of 34.
The number 9 becomes the next digit in our result. 
Result so far: 12738.9629
Subtract 486 from 520 to get 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 11:
340 divided by 54 is 6 with a remainder of 16.
The next digit of our result is 6. 
Result so far: 12738.96296
If we subtract 324 from 340, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 12:
When dividing 160 by 54, we get 2 with a remainder of 52.
Record the quotient 2 as the next digit in the result. 
Result so far: 12738.962962
If we subtract 108 from 160, we 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.

Let's proceed to step 13:
If we divide 520 by 54, we get 9 and a remainder of 34.
Put 9 as the next digit of the answer. 
Result so far: 12738.9629629
The remainder is 34 after subtracting 486 from 520.
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:
When dividing 340 by 54, we get 6 with a remainder of 16.
Write down 6 as next digit of the result. 
Result so far: 12738.96296296
Subtract 324 from 340 to get 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 12738.96296296, with a leftover of 1.6e-08.