We're dividing 421347 by 34 
The aim is to understand the frequency of 34 in 421347.

On to step 1:
34 goes into 4 0 times with a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 34

Going ahead to step 2:
34 can be fit into 42 1 times, resulting in a remainder of 8.
Put 1 as the next digit of the answer. 
Result so far: 1.0
The remainder is 8 after subtracting 34 from 42.
Fetch the next digit (1) from the dividend, attach it to 8 and continue: 81 / 34

On to step 3:
If we divide 81 by 34, we get 2 and a remainder of 13.
Use 2 as the next digit of our solution. 
Result so far: 12.0
Subtracting 68 from 81 leaves us with 13.
Grab the next digit (3) from the dividend, add it to 13, then carry on: 133 / 34

Moving on to step 4:
34 goes into 133 3 times with a remainder of 31.
The number 3 becomes the next digit in our result. 
Result so far: 123.0
If we subtract 102 from 133, we get 31.
Append the next digit (4) from the dividend to 31 and continue with: 314 / 34

Advancing to step 5:
34 goes into 314 9 times with a remainder of 8.
Record the quotient 9 as the next digit in the result. 
Result so far: 1239.0
The remainder is 8 after subtracting 306 from 314.
Take the next digit (7) from the dividend and append it to 8, then repeat: 87 / 34

Going ahead to step 6:
When dividing 87 by 34, we get 2 with a remainder of 19.
Put 2 as the next digit of the answer. 
Result so far: 12392.0
The remainder is 19 after subtracting 68 from 87.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

On to step 7:
The number 34 fits into 190 5 times, leaving a remainder of 20.
Use 5 as the next digit of our solution. 
Result so far: 12392.5
Subtract 170 from 190 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 8:
200 divided by 34 is 5 with a remainder of 30.
Use 5 as the next digit of our solution. 
Result so far: 12392.55
Subtracting 170 from 200 leaves us with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

After the division, we end up with 12392.55 and a remainder of 0.03.