604904 ÷ 3 
The aim is to understand the frequency of 3 in 604904.

On to step 1:
If we divide 6 by 3, we get 2 and a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 2.0
Deduct 6 from 6 and we're left with 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 3

On to step 2:
If we divide 0 by 3, we get 0 and a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 20.0
The remainder is 0 after subtracting 0 from 0.
Fetch the next digit (4) from the dividend, attach it to 0 and continue: 4 / 3

On to step 3:
If we divide 4 by 3, we get 1 and a remainder of 1.
The next digit of our result is 1. 
Result so far: 201.0
The remainder is 1 after subtracting 3 from 4.
Include the next digit (9) from the dividend after 1, then repeat: 19 / 3

Step 4:
3 goes into 19 6 times with a remainder of 1.
Write down 6 as next digit of the result. 
Result so far: 2016.0
If we subtract 18 from 19, we get 1.
Include the next digit (0) from the dividend after 1, then repeat: 10 / 3

Advancing to step 5:
When dividing 10 by 3, we get 3 with a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 20163.0
Subtract 9 from 10 to get 1.
Include the next digit (4) from the dividend after 1, then repeat: 14 / 3

Moving on to step 6:
3 goes into 14 4 times with a remainder of 2.
The number 4 becomes the next digit in our result. 
Result so far: 201634.0
Deduct 12 from 14 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 7:
The number 3 fits into 20 6 times, leaving a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 201634.6
If we subtract 18 from 20, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Advancing to step 8:
If we divide 20 by 3, we get 6 and a remainder of 2.
Put 6 as the next digit of the answer. 
Result so far: 201634.66
The remainder is 2 after subtracting 18 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

After the division, we end up with 201634.66 and a remainder of 0.002.