123420 divided by 42 
Our goal is to divide 123420 by 42.

Let's proceed to step 1:
42 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 42

Going ahead to step 2:
The number 42 fits into 12 0 times, leaving a remainder of 12.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 12 leaves us with 12.
Grab the next digit (3) from the dividend, add it to 12, then carry on: 123 / 42

On to step 3:
123 divided by 42 is 2 with a remainder of 39.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 84 from 123 to get 39.
Fetch the next digit (4) from the dividend, attach it to 39 and continue: 394 / 42

Advancing to step 4:
If we divide 394 by 42, we get 9 and a remainder of 16.
Use 9 as the next digit of our solution. 
Result so far: 29.0
The remainder is 16 after subtracting 378 from 394.
Append the next digit (2) from the dividend to 16 and continue with: 162 / 42

Going ahead to step 5:
162 divided by 42 is 3 with a remainder of 36.
The next digit of our result is 3. 
Result so far: 293.0
If we subtract 126 from 162, we get 36.
Grab the next digit (0) from the dividend, add it to 36, then carry on: 360 / 42

Step 6:
The number 42 fits into 360 8 times, leaving a remainder of 24.
The number 8 becomes the next digit in our result. 
Result so far: 2938.0
Subtracting 336 from 360 leaves us with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Let's proceed to step 7:
42 goes into 240 5 times with a remainder of 30.
Put 5 as the next digit of the answer. 
Result so far: 2938.5
Subtracting 210 from 240 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.

Moving on to step 8:
The number 42 fits into 300 7 times, leaving a remainder of 6.
Write down 7 as next digit of the result. 
Result so far: 2938.57
If we take 294 away from 300, we end up with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Moving on to step 9:
If we divide 60 by 42, we get 1 and a remainder of 18.
Record the quotient 1 as the next digit in the result. 
Result so far: 2938.571
Subtract 42 from 60 to get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 10:
When dividing 180 by 42, we get 4 with a remainder of 12.
The next digit of our result is 4. 
Result so far: 2938.5714
If we subtract 168 from 180, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 11:
When dividing 120 by 42, we get 2 with a remainder of 36.
Write down 2 as next digit of the result. 
Result so far: 2938.57142
The remainder is 36 after subtracting 84 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Step 12:
360 divided by 42 is 8 with a remainder of 24.
Put 8 as the next digit of the answer. 
Result so far: 2938.571428
Subtracting 336 from 360 leaves us with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Step 13:
42 can be fit into 240 5 times, resulting in a remainder of 30.
Use 5 as the next digit of our solution. 
Result so far: 2938.5714285
Subtract 210 from 240 to get 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Advancing to step 14:
The number 42 fits into 300 7 times, leaving a remainder of 6.
Put 7 as the next digit of the answer. 
Result so far: 2938.57142857
Subtracting 294 from 300 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Our division results in 2938.57142857 with a remaining 6e-09.