Let's divide 420353 by 15
We want to divide 420353 by 15.

On to step 1:
If we divide 4 by 15, we get 0 and a remainder of 4.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 4, we get 4.
Take the next digit (2) from the dividend and append it to 4, then repeat: 42 / 15

Advancing to step 2:
15 goes into 42 2 times with a remainder of 12.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Deduct 30 from 42 and we're left with 12.
Bring next digit (0) of the dividend behind the 12 and repeat the process: 120 / 15

Moving on to step 3:
The number 15 fits into 120 8 times, leaving a remainder of 0.
Use 8 as the next digit of our solution. 
Result so far: 28.0
Deduct 120 from 120 and we're left with 0.
Take the next digit (3) from the dividend and append it to 0, then repeat: 3 / 15

Going ahead to step 4:
When dividing 3 by 15, we get 0 with a remainder of 3.
The next digit of our result is 0. 
Result so far: 280.0
If we subtract 0 from 3, we get 3.
Grab the next digit (5) from the dividend, add it to 3, then carry on: 35 / 15

On to step 5:
The number 15 fits into 35 2 times, leaving a remainder of 5.
Use 2 as the next digit of our solution. 
Result so far: 2802.0
If we take 30 away from 35, we end up with 5.
Append the next digit (3) from the dividend to 5 and continue with: 53 / 15

Moving on to step 6:
If we divide 53 by 15, we get 3 and a remainder of 8.
Record the quotient 3 as the next digit in the result. 
Result so far: 28023.0
Subtracting 45 from 53 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.

Step 7:
15 goes into 80 5 times with a remainder of 5.
The next digit of our result is 5. 
Result so far: 28023.5
Subtracting 75 from 80 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.

On to step 8:
50 divided by 15 is 3 with a remainder of 5.
Put 3 as the next digit of the answer. 
Result so far: 28023.53
If we take 45 away from 50, we end up 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.

Advancing to step 9:
The number 15 fits into 50 3 times, leaving a remainder of 5.
Put 3 as the next digit of the answer. 
Result so far: 28023.533
Deduct 45 from 50 and we're left 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.

After the division, we end up with 28023.533 and a remainder of 0.0005.