We look at the division of 81646870 by 678 
The aim is to understand the frequency of 678 in 81646870.

On to step 1:
678 can be fit into 8 0 times, resulting in a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Bring next digit (1) of the dividend behind the 8 and repeat the process: 81 / 678

On to step 2:
678 goes into 81 0 times with a remainder of 81.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 81 leaves us with 81.
Append the next digit (6) from the dividend to 81 and continue with: 816 / 678

Going ahead to step 3:
678 can be fit into 816 1 times, resulting in a remainder of 138.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 138 after subtracting 678 from 816.
Include the next digit (4) from the dividend after 138, then repeat: 1384 / 678

Step 4:
678 can be fit into 1384 2 times, resulting in a remainder of 28.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
The remainder is 28 after subtracting 1356 from 1384.
Bring next digit (6) of the dividend behind the 28 and repeat the process: 286 / 678

Advancing to step 5:
678 can be fit into 286 0 times, resulting in a remainder of 286.
Record the quotient 0 as the next digit in the result. 
Result so far: 120.0
The remainder is 286 after subtracting 0 from 286.
Append the next digit (8) from the dividend to 286 and continue with: 2868 / 678

Let's proceed to step 6:
678 can be fit into 2868 4 times, resulting in a remainder of 156.
Put 4 as the next digit of the answer. 
Result so far: 1204.0
Deduct 2712 from 2868 and we're left with 156.
Fetch the next digit (7) from the dividend, attach it to 156 and continue: 1567 / 678

Moving on to step 7:
If we divide 1567 by 678, we get 2 and a remainder of 211.
The next digit of our result is 2. 
Result so far: 12042.0
The remainder is 211 after subtracting 1356 from 1567.
Include the next digit (0) from the dividend after 211, then repeat: 2110 / 678

On to step 8:
678 can be fit into 2110 3 times, resulting in a remainder of 76.
Write down 3 as next digit of the result. 
Result so far: 120423.0
Deduct 2034 from 2110 and we're left with 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

On to step 9:
678 can be fit into 760 1 times, resulting in a remainder of 82.
Write down 1 as next digit of the result. 
Result so far: 120423.1
The remainder is 82 after subtracting 678 from 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 820, and continue the process.

On to step 10:
678 goes into 820 1 times with a remainder of 142.
Write down 1 as next digit of the result. 
Result so far: 120423.11
If we take 678 away from 820, we end up with 142.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1420, and continue the process.

In conclusion, the division gives 120423.11 with a balance of 0.142.