Let's divide 142391 by 31
We want to figure out the number of times 142391 can be divided by 31.

Step 1:
31 goes into 1 0 times with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Append the next digit (4) from the dividend to 1 and continue with: 14 / 31

On to step 2:
The number 31 fits into 14 0 times, leaving a remainder of 14.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 14, we end up with 14.
Grab the next digit (2) from the dividend, add it to 14, then carry on: 142 / 31

On to step 3:
31 can be fit into 142 4 times, resulting in a remainder of 18.
Put 4 as the next digit of the answer. 
Result so far: 4.0
If we subtract 124 from 142, we get 18.
Grab the next digit (3) from the dividend, add it to 18, then carry on: 183 / 31

On to step 4:
The number 31 fits into 183 5 times, leaving a remainder of 28.
The next digit of our result is 5. 
Result so far: 45.0
Deduct 155 from 183 and we're left with 28.
Bring next digit (9) of the dividend behind the 28 and repeat the process: 289 / 31

On to step 5:
31 can be fit into 289 9 times, resulting in a remainder of 10.
The number 9 becomes the next digit in our result. 
Result so far: 459.0
Subtract 279 from 289 to get 10.
Include the next digit (1) from the dividend after 10, then repeat: 101 / 31

Let's proceed to step 6:
When dividing 101 by 31, we get 3 with a remainder of 8.
The next digit of our result is 3. 
Result so far: 4593.0
Subtract 93 from 101 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.

Advancing to step 7:
The number 31 fits into 80 2 times, leaving a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 4593.2
If we subtract 62 from 80, we 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.

On to step 8:
31 can be fit into 180 5 times, resulting in a remainder of 25.
Use 5 as the next digit of our solution. 
Result so far: 4593.25
The remainder is 25 after subtracting 155 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Moving on to step 9:
If we divide 250 by 31, we get 8 and a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 4593.258
Subtract 248 from 250 to 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.

On to step 10:
When dividing 20 by 31, we get 0 with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 4593.258
Subtract 0 from 20 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.

Going ahead to step 11:
The number 31 fits into 200 6 times, leaving a remainder of 14.
Use 6 as the next digit of our solution. 
Result so far: 4593.25806
Deduct 186 from 200 and we're left with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 12:
140 divided by 31 is 4 with a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 4593.258064
Deduct 124 from 140 and we're left with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 13:
160 divided by 31 is 5 with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 4593.2580645
Subtracting 155 from 160 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 14:
31 can be fit into 50 1 times, resulting in a remainder of 19.
Write down 1 as next digit of the result. 
Result so far: 4593.25806451
Deduct 31 from 50 and we're left 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.

The final outcome is 4593.25806451, with a leftover of 1.9e-08.