We look at the division of 345401 by 3 
The aim is to understand the frequency of 3 in 345401.

Let's proceed to step 1:
3 divided by 3 is 1 with a remainder of 0.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we take 3 away from 3, we end up with 0.
Fetch the next digit (4) from the dividend, attach it to 0 and continue: 4 / 3

Advancing to step 2:
3 goes into 4 1 times with a remainder of 1.
Record the quotient 1 as the next digit in the result. 
Result so far: 11.0
Deduct 3 from 4 and we're left with 1.
Grab the next digit (5) from the dividend, add it to 1, then carry on: 15 / 3

On to step 3:
3 goes into 15 5 times with a remainder of 0.
The next digit of our result is 5. 
Result so far: 115.0
If we subtract 15 from 15, we get 0.
Include the next digit (4) from the dividend after 0, then repeat: 4 / 3

Going ahead to step 4:
4 divided by 3 is 1 with a remainder of 1.
Record the quotient 1 as the next digit in the result. 
Result so far: 1151.0
Subtracting 3 from 4 leaves us with 1.
Grab the next digit (0) from the dividend, add it to 1, then carry on: 10 / 3

Moving on to step 5:
3 can be fit into 10 3 times, resulting in a remainder of 1.
Record the quotient 3 as the next digit in the result. 
Result so far: 11513.0
If we subtract 9 from 10, we get 1.
Include the next digit (1) from the dividend after 1, then repeat: 11 / 3

Let's proceed to step 6:
3 goes into 11 3 times with a remainder of 2.
Put 3 as the next digit of the answer. 
Result so far: 115133.0
The remainder is 2 after subtracting 9 from 11.
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:
20 divided by 3 is 6 with a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 115133.6
Subtracting 18 from 20 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 8:
3 goes into 20 6 times with a remainder of 2.
Write down 6 as next digit of the result. 
Result so far: 115133.66
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.

The quotient of the division is 115133.66, and the remainder is 0.002.