We look at the division of 689100 by 78 
The aim is to understand the frequency of 78 in 689100.

Step 1:
6 divided by 78 is 0 with a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Include the next digit (8) from the dividend after 6, then repeat: 68 / 78

On to step 2:
78 goes into 68 0 times with a remainder of 68.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 68 and we're left with 68.
Include the next digit (9) from the dividend after 68, then repeat: 689 / 78

On to step 3:
When dividing 689 by 78, we get 8 with a remainder of 65.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
Subtracting 624 from 689 leaves us with 65.
Fetch the next digit (1) from the dividend, attach it to 65 and continue: 651 / 78

On to step 4:
78 goes into 651 8 times with a remainder of 27.
The next digit of our result is 8. 
Result so far: 88.0
Subtracting 624 from 651 leaves us with 27.
Append the next digit (0) from the dividend to 27 and continue with: 270 / 78

Step 5:
When dividing 270 by 78, we get 3 with a remainder of 36.
Write down 3 as next digit of the result. 
Result so far: 883.0
The remainder is 36 after subtracting 234 from 270.
Take the next digit (0) from the dividend and append it to 36, then repeat: 360 / 78

Let's proceed to step 6:
360 divided by 78 is 4 with a remainder of 48.
Use 4 as the next digit of our solution. 
Result so far: 8834.0
If we take 312 away from 360, we end up with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Advancing to step 7:
78 goes into 480 6 times with a remainder of 12.
Use 6 as the next digit of our solution. 
Result so far: 8834.6
Subtracting 468 from 480 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 8:
78 goes into 120 1 times with a remainder of 42.
Record the quotient 1 as the next digit in the result. 
Result so far: 8834.61
Subtract 78 from 120 to get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

On to step 9:
When dividing 420 by 78, we get 5 with a remainder of 30.
The next digit of our result is 5. 
Result so far: 8834.615
Subtract 390 from 420 to get 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

On to step 10:
78 goes into 300 3 times with a remainder of 66.
Write down 3 as next digit of the result. 
Result so far: 8834.6153
If we take 234 away from 300, we end up with 66.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

Step 11:
78 goes into 660 8 times with a remainder of 36.
The number 8 becomes the next digit in our result. 
Result so far: 8834.61538
The remainder is 36 after subtracting 624 from 660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Moving on to step 12:
360 divided by 78 is 4 with a remainder of 48.
The number 4 becomes the next digit in our result. 
Result so far: 8834.615384
Deduct 312 from 360 and we're left with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Moving on to step 13:
480 divided by 78 is 6 with a remainder of 12.
Record the quotient 6 as the next digit in the result. 
Result so far: 8834.6153846
Subtract 468 from 480 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 14:
When dividing 120 by 78, we get 1 with a remainder of 42.
Record the quotient 1 as the next digit in the result. 
Result so far: 8834.61538461
Subtract 78 from 120 to get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

The final outcome is 8834.61538461, with a leftover of 4.2e-08.