Let's divide 621915 by 45
We're looking to find how many times 45 goes into 621915.

Step 1:
45 goes into 6 0 times with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Bring next digit (2) of the dividend behind the 6 and repeat the process: 62 / 45

Moving on to step 2:
The number 45 fits into 62 1 times, leaving a remainder of 17.
The next digit of our result is 1. 
Result so far: 1.0
The remainder is 17 after subtracting 45 from 62.
Bring next digit (1) of the dividend behind the 17 and repeat the process: 171 / 45

On to step 3:
171 divided by 45 is 3 with a remainder of 36.
The next digit of our result is 3. 
Result so far: 13.0
Subtracting 135 from 171 leaves us with 36.
Include the next digit (9) from the dividend after 36, then repeat: 369 / 45

Let's proceed to step 4:
The number 45 fits into 369 8 times, leaving a remainder of 9.
Use 8 as the next digit of our solution. 
Result so far: 138.0
Subtract 360 from 369 to get 9.
Include the next digit (1) from the dividend after 9, then repeat: 91 / 45

Let's proceed to step 5:
45 goes into 91 2 times with a remainder of 1.
Record the quotient 2 as the next digit in the result. 
Result so far: 1382.0
Subtracting 90 from 91 leaves us with 1.
Append the next digit (5) from the dividend to 1 and continue with: 15 / 45

Step 6:
The number 45 fits into 15 0 times, leaving a remainder of 15.
Record the quotient 0 as the next digit in the result. 
Result so far: 13820.0
Subtracting 0 from 15 leaves us with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Advancing to step 7:
If we divide 150 by 45, we get 3 and a remainder of 15.
Record the quotient 3 as the next digit in the result. 
Result so far: 13820.3
Deduct 135 from 150 and we're left with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Step 8:
45 can be fit into 150 3 times, resulting in a remainder of 15.
The number 3 becomes the next digit in our result. 
Result so far: 13820.33
If we take 135 away from 150, we end up with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

The final result is 13820.33 with a remainder of 0.015.