We look at the division of 646726 by 3 
The aim is to understand the frequency of 3 in 646726.

Going ahead 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.
Fetch the next digit (4) from the dividend, attach it to 0 and continue: 4 / 3

On to step 2:
3 goes into 4 1 times with a remainder of 1.
The number 1 becomes the next digit in our result. 
Result so far: 21.0
Subtract 3 from 4 to get 1.
Include the next digit (6) from the dividend after 1, then repeat: 16 / 3

Step 3:
When dividing 16 by 3, we get 5 with a remainder of 1.
Write down 5 as next digit of the result. 
Result so far: 215.0
Subtract 15 from 16 to get 1.
Include the next digit (7) from the dividend after 1, then repeat: 17 / 3

Going ahead to step 4:
If we divide 17 by 3, we get 5 and a remainder of 2.
Put 5 as the next digit of the answer. 
Result so far: 2155.0
Subtract 15 from 17 to get 2.
Append the next digit (2) from the dividend to 2 and continue with: 22 / 3

Let's proceed to step 5:
If we divide 22 by 3, we get 7 and a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 21557.0
Subtracting 21 from 22 leaves us with 1.
Fetch the next digit (6) from the dividend, attach it to 1 and continue: 16 / 3

Going ahead to step 6:
3 goes into 16 5 times with a remainder of 1.
Put 5 as the next digit of the answer. 
Result so far: 215575.0
The remainder is 1 after subtracting 15 from 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Step 7:
3 goes into 10 3 times with a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 215575.3
If we subtract 9 from 10, 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.

Going ahead to step 8:
When dividing 10 by 3, we get 3 with a remainder of 1.
Put 3 as the next digit of the answer. 
Result so far: 215575.33
Subtract 9 from 10 to 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.

Our division results in 215575.33 with a remaining 0.001.