We look at the division of 813878 by 4 
The aim is to understand the frequency of 4 in 813878.

On to step 1:
If we divide 8 by 4, we get 2 and a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Deduct 8 from 8 and we're left with 0.
Fetch the next digit (1) from the dividend, attach it to 0 and continue: 1 / 4

Moving on to step 2:
The number 4 fits into 1 0 times, leaving a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 20.0
The remainder is 1 after subtracting 0 from 1.
Fetch the next digit (3) from the dividend, attach it to 1 and continue: 13 / 4

Step 3:
4 can be fit into 13 3 times, resulting in a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 203.0
If we subtract 12 from 13, we get 1.
Fetch the next digit (8) from the dividend, attach it to 1 and continue: 18 / 4

Advancing to step 4:
4 goes into 18 4 times with a remainder of 2.
The next digit of our result is 4. 
Result so far: 2034.0
If we subtract 16 from 18, we get 2.
Grab the next digit (7) from the dividend, add it to 2, then carry on: 27 / 4

Let's proceed to step 5:
4 goes into 27 6 times with a remainder of 3.
Write down 6 as next digit of the result. 
Result so far: 20346.0
If we take 24 away from 27, we end up with 3.
Take the next digit (8) from the dividend and append it to 3, then repeat: 38 / 4

On to step 6:
The number 4 fits into 38 9 times, leaving a remainder of 2.
The number 9 becomes the next digit in our result. 
Result so far: 203469.0
The remainder is 2 after subtracting 36 from 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 7:
4 can be fit into 20 5 times, resulting in a remainder of 0.
The number 5 becomes the next digit in our result. 
Result so far: 203469.5
Deduct 20 from 20 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 8:
The number 4 fits into 0 0 times, leaving a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 203469.5
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 9:
4 goes into 0 0 times with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 203469.5
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The quotient of the division is 203469.5, and the remainder is 0.0.