Let's divide 391543 by 42
Our goal is to divide 391543 by 42.

Step 1:
42 can be fit into 3 0 times, resulting in a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 42

Advancing to step 2:
When dividing 39 by 42, we get 0 with a remainder of 39.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 39 leaves us with 39.
Bring next digit (1) of the dividend behind the 39 and repeat the process: 391 / 42

Advancing to step 3:
42 can be fit into 391 9 times, resulting in a remainder of 13.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
If we subtract 378 from 391, we get 13.
Bring next digit (5) of the dividend behind the 13 and repeat the process: 135 / 42

Let's proceed to step 4:
42 can be fit into 135 3 times, resulting in a remainder of 9.
Record the quotient 3 as the next digit in the result. 
Result so far: 93.0
If we take 126 away from 135, we end up with 9.
Fetch the next digit (4) from the dividend, attach it to 9 and continue: 94 / 42

Advancing to step 5:
When dividing 94 by 42, we get 2 with a remainder of 10.
Put 2 as the next digit of the answer. 
Result so far: 932.0
The remainder is 10 after subtracting 84 from 94.
Take the next digit (3) from the dividend and append it to 10, then repeat: 103 / 42

Advancing to step 6:
42 goes into 103 2 times with a remainder of 19.
Record the quotient 2 as the next digit in the result. 
Result so far: 9322.0
Subtracting 84 from 103 leaves us with 19.
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:
190 divided by 42 is 4 with a remainder of 22.
Use 4 as the next digit of our solution. 
Result so far: 9322.4
Subtract 168 from 190 to get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Going ahead to step 8:
220 divided by 42 is 5 with a remainder of 10.
The next digit of our result is 5. 
Result so far: 9322.45
Subtracting 210 from 220 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 9:
The number 42 fits into 100 2 times, leaving a remainder of 16.
The number 2 becomes the next digit in our result. 
Result so far: 9322.452
If we subtract 84 from 100, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 10:
The number 42 fits into 160 3 times, leaving a remainder of 34.
Write down 3 as next digit of the result. 
Result so far: 9322.4523
Deduct 126 from 160 and we're left with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Step 11:
340 divided by 42 is 8 with a remainder of 4.
Put 8 as the next digit of the answer. 
Result so far: 9322.45238
Subtract 336 from 340 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 12:
40 divided by 42 is 0 with a remainder of 40.
Use 0 as the next digit of our solution. 
Result so far: 9322.45238
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 13:
If we divide 400 by 42, we get 9 and a remainder of 22.
Put 9 as the next digit of the answer. 
Result so far: 9322.4523809
Deduct 378 from 400 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Advancing to step 14:
If we divide 220 by 42, we get 5 and a remainder of 10.
The number 5 becomes the next digit in our result. 
Result so far: 9322.45238095
The remainder is 10 after subtracting 210 from 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final outcome is 9322.45238095, with a leftover of 1e-08.