We look at the division of 15157999 by 421 
We want to divide 15157999 by 421.

Let's proceed to step 1:
When dividing 1 by 421, we get 0 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.
Include the next digit (5) from the dividend after 1, then repeat: 15 / 421

Moving on to step 2:
421 goes into 15 0 times with a remainder of 15.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 15, we get 15.
Bring next digit (1) of the dividend behind the 15 and repeat the process: 151 / 421

Let's proceed to step 3:
421 goes into 151 0 times with a remainder of 151.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 151 to get 151.
Fetch the next digit (5) from the dividend, attach it to 151 and continue: 1515 / 421

On to step 4:
When dividing 1515 by 421, we get 3 with a remainder of 252.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
Subtracting 1263 from 1515 leaves us with 252.
Append the next digit (7) from the dividend to 252 and continue with: 2527 / 421

Step 5:
When dividing 2527 by 421, we get 6 with a remainder of 1.
The number 6 becomes the next digit in our result. 
Result so far: 36.0
If we take 2526 away from 2527, we end up with 1.
Fetch the next digit (9) from the dividend, attach it to 1 and continue: 19 / 421

Step 6:
If we divide 19 by 421, we get 0 and a remainder of 19.
Put 0 as the next digit of the answer. 
Result so far: 360.0
Subtracting 0 from 19 leaves us with 19.
Include the next digit (9) from the dividend after 19, then repeat: 199 / 421

Step 7:
421 goes into 199 0 times with a remainder of 199.
Record the quotient 0 as the next digit in the result. 
Result so far: 3600.0
If we take 0 away from 199, we end up with 199.
Take the next digit (9) from the dividend and append it to 199, then repeat: 1999 / 421

Moving on to step 8:
When dividing 1999 by 421, we get 4 with a remainder of 315.
Put 4 as the next digit of the answer. 
Result so far: 36004.0
If we subtract 1684 from 1999, we get 315.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3150, and continue the process.

Advancing to step 9:
421 can be fit into 3150 7 times, resulting in a remainder of 203.
Record the quotient 7 as the next digit in the result. 
Result so far: 36004.7
If we take 2947 away from 3150, we end up with 203.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2030, and continue the process.

Going ahead to step 10:
The number 421 fits into 2030 4 times, leaving a remainder of 346.
Write down 4 as next digit of the result. 
Result so far: 36004.74
If we take 1684 away from 2030, we end up with 346.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3460, and continue the process.

Going ahead to step 11:
When dividing 3460 by 421, we get 8 with a remainder of 92.
Write down 8 as next digit of the result. 
Result so far: 36004.748
Subtracting 3368 from 3460 leaves us with 92.
Since there are no more digits in the dividend, we add a zero to the remainder making it 920, and continue the process.

Moving on to step 12:
421 goes into 920 2 times with a remainder of 78.
Write down 2 as next digit of the result. 
Result so far: 36004.7482
Deduct 842 from 920 and we're left with 78.
Since there are no more digits in the dividend, we add a zero to the remainder making it 780, and continue the process.

Step 13:
421 goes into 780 1 times with a remainder of 359.
Use 1 as the next digit of our solution. 
Result so far: 36004.74821
Subtract 421 from 780 to get 359.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3590, and continue the process.

Advancing to step 14:
The number 421 fits into 3590 8 times, leaving a remainder of 222.
The number 8 becomes the next digit in our result. 
Result so far: 36004.748218
Subtract 3368 from 3590 to get 222.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2220, and continue the process.

Going ahead to step 15:
2220 divided by 421 is 5 with a remainder of 115.
The next digit of our result is 5. 
Result so far: 36004.7482185
Subtracting 2105 from 2220 leaves us with 115.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1150, and continue the process.

Advancing to step 16:
421 can be fit into 1150 2 times, resulting in a remainder of 308.
Record the quotient 2 as the next digit in the result. 
Result so far: 36004.74821852
The remainder is 308 after subtracting 842 from 1150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3080, and continue the process.

Our division results in 36004.74821852 with a remaining 3.08e-07.