We look at the division of 578830 by 78 
The aim is to understand the frequency of 78 in 578830.

On to step 1:
When dividing 5 by 78, we get 0 with a remainder of 5.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Bring next digit (7) of the dividend behind the 5 and repeat the process: 57 / 78

Let's proceed to step 2:
78 goes into 57 0 times with a remainder of 57.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 57, we end up with 57.
Append the next digit (8) from the dividend to 57 and continue with: 578 / 78

Going ahead to step 3:
If we divide 578 by 78, we get 7 and a remainder of 32.
Write down 7 as next digit of the result. 
Result so far: 7.0
If we subtract 546 from 578, we get 32.
Grab the next digit (8) from the dividend, add it to 32, then carry on: 328 / 78

Let's proceed to step 4:
When dividing 328 by 78, we get 4 with a remainder of 16.
The number 4 becomes the next digit in our result. 
Result so far: 74.0
Subtracting 312 from 328 leaves us with 16.
Append the next digit (3) from the dividend to 16 and continue with: 163 / 78

Let's proceed to step 5:
78 can be fit into 163 2 times, resulting in a remainder of 7.
The number 2 becomes the next digit in our result. 
Result so far: 742.0
The remainder is 7 after subtracting 156 from 163.
Take the next digit (0) from the dividend and append it to 7, then repeat: 70 / 78

Advancing to step 6:
If we divide 70 by 78, we get 0 and a remainder of 70.
Write down 0 as next digit of the result. 
Result so far: 7420.0
If we subtract 0 from 70, we get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

On to step 7:
The number 78 fits into 700 8 times, leaving a remainder of 76.
The number 8 becomes the next digit in our result. 
Result so far: 7420.8
If we subtract 624 from 700, we get 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Moving on to step 8:
760 divided by 78 is 9 with a remainder of 58.
The number 9 becomes the next digit in our result. 
Result so far: 7420.89
Subtracting 702 from 760 leaves us with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Moving on to step 9:
If we divide 580 by 78, we get 7 and a remainder of 34.
The next digit of our result is 7. 
Result so far: 7420.897
Deduct 546 from 580 and we're left 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.

On to step 10:
78 can be fit into 340 4 times, resulting in a remainder of 28.
Record the quotient 4 as the next digit in the result. 
Result so far: 7420.8974
If we take 312 away from 340, we end up with 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Moving on to step 11:
If we divide 280 by 78, we get 3 and a remainder of 46.
Record the quotient 3 as the next digit in the result. 
Result so far: 7420.89743
If we subtract 234 from 280, we get 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

Going ahead to step 12:
78 goes into 460 5 times with a remainder of 70.
Put 5 as the next digit of the answer. 
Result so far: 7420.897435
Subtract 390 from 460 to get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Advancing to step 13:
If we divide 700 by 78, we get 8 and a remainder of 76.
The next digit of our result is 8. 
Result so far: 7420.8974358
If we subtract 624 from 700, we get 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 14:
78 can be fit into 760 9 times, resulting in a remainder of 58.
Record the quotient 9 as the next digit in the result. 
Result so far: 7420.89743589
The remainder is 58 after subtracting 702 from 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

The final outcome is 7420.89743589, with a leftover of 5.8e-08.