We look at the division of 542543 by 12 
Our goal is to divide 542543 by 12.

Step 1:
When dividing 5 by 12, we get 0 with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 5, we end up with 5.
Append the next digit (4) from the dividend to 5 and continue with: 54 / 12

Advancing to step 2:
If we divide 54 by 12, we get 4 and a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
Subtracting 48 from 54 leaves us with 6.
Include the next digit (2) from the dividend after 6, then repeat: 62 / 12

Step 3:
12 can be fit into 62 5 times, resulting in a remainder of 2.
Record the quotient 5 as the next digit in the result. 
Result so far: 45.0
Subtracting 60 from 62 leaves us with 2.
Append the next digit (5) from the dividend to 2 and continue with: 25 / 12

Moving on to step 4:
If we divide 25 by 12, we get 2 and a remainder of 1.
The number 2 becomes the next digit in our result. 
Result so far: 452.0
Deduct 24 from 25 and we're left with 1.
Include the next digit (4) from the dividend after 1, then repeat: 14 / 12

Moving on to step 5:
12 goes into 14 1 times with a remainder of 2.
Put 1 as the next digit of the answer. 
Result so far: 4521.0
Deduct 12 from 14 and we're left with 2.
Append the next digit (3) from the dividend to 2 and continue with: 23 / 12

On to step 6:
The number 12 fits into 23 1 times, leaving a remainder of 11.
Use 1 as the next digit of our solution. 
Result so far: 45211.0
Subtract 12 from 23 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Moving on to step 7:
110 divided by 12 is 9 with a remainder of 2.
Write down 9 as next digit of the result. 
Result so far: 45211.9
If we subtract 108 from 110, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 8:
If we divide 20 by 12, we get 1 and a remainder of 8.
Record the quotient 1 as the next digit in the result. 
Result so far: 45211.91
Subtract 12 from 20 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 9:
If we divide 80 by 12, we get 6 and a remainder of 8.
Write down 6 as next digit of the result. 
Result so far: 45211.916
Subtracting 72 from 80 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 10:
The number 12 fits into 80 6 times, leaving a remainder of 8.
The number 6 becomes the next digit in our result. 
Result so far: 45211.9166
If we subtract 72 from 80, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

The final outcome is 45211.9166, with a leftover of 8e-05.