We look at the division of 451234 by 3 
Let's see how many times 3 fits into 451234.

Let's proceed to step 1:
If we divide 4 by 3, we get 1 and a remainder of 1.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we take 3 away from 4, we end up with 1.
Include the next digit (5) from the dividend after 1, then repeat: 15 / 3

Going ahead to step 2:
If we divide 15 by 3, we get 5 and a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 15.0
If we take 15 away from 15, we end up with 0.
Grab the next digit (1) from the dividend, add it to 0, then carry on: 1 / 3

Step 3:
1 divided by 3 is 0 with a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 150.0
Subtract 0 from 1 to get 1.
Grab the next digit (2) from the dividend, add it to 1, then carry on: 12 / 3

Advancing to step 4:
3 can be fit into 12 4 times, resulting in a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 1504.0
The remainder is 0 after subtracting 12 from 12.
Take the next digit (3) from the dividend and append it to 0, then repeat: 3 / 3

Let's proceed to step 5:
3 goes into 3 1 times with a remainder of 0.
Record the quotient 1 as the next digit in the result. 
Result so far: 15041.0
Deduct 3 from 3 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 6:
3 can be fit into 4 1 times, resulting in a remainder of 1.
Use 1 as the next digit of our solution. 
Result so far: 150411.0
Subtract 3 from 4 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.

Let's proceed to step 7:
3 can be fit into 10 3 times, resulting in a remainder of 1.
Use 3 as the next digit of our solution. 
Result so far: 150411.3
If we take 9 away from 10, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Advancing to step 8:
The number 3 fits into 10 3 times, leaving a remainder of 1.
The next digit of our result is 3. 
Result so far: 150411.33
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.

Our division results in 150411.33 with a remaining 0.001.