518113 ÷ 3 
The aim is to understand the frequency of 3 in 518113.

Step 1:
3 goes into 5 1 times with a remainder of 2.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we subtract 3 from 5, we get 2.
Fetch the next digit (1) from the dividend, attach it to 2 and continue: 21 / 3

Moving on to step 2:
21 divided by 3 is 7 with a remainder of 0.
Use 7 as the next digit of our solution. 
Result so far: 17.0
The remainder is 0 after subtracting 21 from 21.
Bring next digit (8) of the dividend behind the 0 and repeat the process: 8 / 3

On to step 3:
8 divided by 3 is 2 with a remainder of 2.
Write down 2 as next digit of the result. 
Result so far: 172.0
Subtracting 6 from 8 leaves us with 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 3

On to step 4:
3 can be fit into 21 7 times, resulting in a remainder of 0.
Write down 7 as next digit of the result. 
Result so far: 1727.0
If we take 21 away from 21, we end up with 0.
Fetch the next digit (1) from the dividend, attach it to 0 and continue: 1 / 3

Moving on to step 5:
3 can be fit into 1 0 times, resulting in a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 17270.0
Subtract 0 from 1 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 3

Step 6:
When dividing 13 by 3, we get 4 with a remainder of 1.
The next digit of our result is 4. 
Result so far: 172704.0
If we subtract 12 from 13, we get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 7:
3 goes into 10 3 times with a remainder of 1.
Record the quotient 3 as the next digit in the result. 
Result so far: 172704.3
Deduct 9 from 10 and we're left with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Advancing to step 8:
The number 3 fits into 10 3 times, leaving a remainder of 1.
Put 3 as the next digit of the answer. 
Result so far: 172704.33
Deduct 9 from 10 and we're left with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Our division results in 172704.33 with a remaining 0.001.