We're dividing 251484 by 20 
Let's see how many times 20 fits into 251484.

Advancing to step 1:
The number 20 fits into 2 0 times, leaving a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Fetch the next digit (5) from the dividend, attach it to 2 and continue: 25 / 20

On to step 2:
The number 20 fits into 25 1 times, leaving a remainder of 5.
Use 1 as the next digit of our solution. 
Result so far: 1.0
If we subtract 20 from 25, we get 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 20

Step 3:
The number 20 fits into 51 2 times, leaving a remainder of 11.
Put 2 as the next digit of the answer. 
Result so far: 12.0
Subtracting 40 from 51 leaves us with 11.
Fetch the next digit (4) from the dividend, attach it to 11 and continue: 114 / 20

Advancing to step 4:
20 can be fit into 114 5 times, resulting in a remainder of 14.
Put 5 as the next digit of the answer. 
Result so far: 125.0
Subtract 100 from 114 to get 14.
Fetch the next digit (8) from the dividend, attach it to 14 and continue: 148 / 20

Step 5:
20 goes into 148 7 times with a remainder of 8.
Record the quotient 7 as the next digit in the result. 
Result so far: 1257.0
Subtract 140 from 148 to get 8.
Take the next digit (4) from the dividend and append it to 8, then repeat: 84 / 20

Advancing to step 6:
The number 20 fits into 84 4 times, leaving a remainder of 4.
The next digit of our result is 4. 
Result so far: 12574.0
If we take 80 away from 84, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 7:
20 can be fit into 40 2 times, resulting in a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 12574.2
The remainder is 0 after subtracting 40 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
0 divided by 20 is 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 12574.2
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 9:
If we divide 0 by 20, we get 0 and a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 12574.2
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 12574.2, with a leftover of 0.0.