765209 ÷ 3 
The aim is to understand the frequency of 3 in 765209.

Advancing to step 1:
3 can be fit into 7 2 times, resulting in a remainder of 1.
Write down 2 as next digit of the result. 
Result so far: 2.0
Deduct 6 from 7 and we're left with 1.
Fetch the next digit (6) from the dividend, attach it to 1 and continue: 16 / 3

Step 2:
The number 3 fits into 16 5 times, leaving a remainder of 1.
Record the quotient 5 as the next digit in the result. 
Result so far: 25.0
If we subtract 15 from 16, we get 1.
Grab the next digit (5) from the dividend, add it to 1, then carry on: 15 / 3

On to step 3:
If we divide 15 by 3, we get 5 and a remainder of 0.
Use 5 as the next digit of our solution. 
Result so far: 255.0
If we take 15 away from 15, we end up with 0.
Bring next digit (2) of the dividend behind the 0 and repeat the process: 2 / 3

Let's proceed to step 4:
3 goes into 2 0 times with a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 2550.0
The remainder is 2 after subtracting 0 from 2.
Take the next digit (0) from the dividend and append it to 2, then repeat: 20 / 3

On to step 5:
3 goes into 20 6 times with a remainder of 2.
The number 6 becomes the next digit in our result. 
Result so far: 25506.0
Subtracting 18 from 20 leaves us with 2.
Grab the next digit (9) from the dividend, add it to 2, then carry on: 29 / 3

Moving on to step 6:
3 can be fit into 29 9 times, resulting in a remainder of 2.
Put 9 as the next digit of the answer. 
Result so far: 255069.0
Deduct 27 from 29 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.

Advancing to step 7:
If we divide 20 by 3, we get 6 and a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 255069.6
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.

On to step 8:
3 can be fit into 20 6 times, resulting in a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 255069.66
Subtract 18 from 20 to 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.

The final result is 255069.66 with a remainder of 0.002.