We're dividing 423146 by 3 
The aim is to understand the frequency of 3 in 423146.

Going ahead to step 1:
The number 3 fits into 4 1 times, leaving a remainder of 1.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Deduct 3 from 4 and we're left with 1.
Append the next digit (2) from the dividend to 1 and continue with: 12 / 3

Advancing to step 2:
If we divide 12 by 3, we get 4 and a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 14.0
Subtracting 12 from 12 leaves us with 0.
Take the next digit (3) from the dividend and append it to 0, then repeat: 3 / 3

On to step 3:
3 divided by 3 is 1 with a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 141.0
The remainder is 0 after subtracting 3 from 3.
Take the next digit (1) from the dividend and append it to 0, then repeat: 1 / 3

Going ahead to step 4:
If we divide 1 by 3, we get 0 and a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 1410.0
The remainder is 1 after subtracting 0 from 1.
Append the next digit (4) from the dividend to 1 and continue with: 14 / 3

Advancing to step 5:
When dividing 14 by 3, we get 4 with a remainder of 2.
Put 4 as the next digit of the answer. 
Result so far: 14104.0
If we subtract 12 from 14, we get 2.
Append the next digit (6) from the dividend to 2 and continue with: 26 / 3

On to step 6:
When dividing 26 by 3, we get 8 with a remainder of 2.
The next digit of our result is 8. 
Result so far: 141048.0
Subtracting 24 from 26 leaves us 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.

Going ahead to step 7:
3 goes into 20 6 times with a remainder of 2.
Use 6 as the next digit of our solution. 
Result so far: 141048.6
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.

Going ahead to step 8:
If we divide 20 by 3, we get 6 and a remainder of 2.
The next digit of our result is 6. 
Result so far: 141048.66
Deduct 18 from 20 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.

The final outcome is 141048.66, with a leftover of 0.002.