We look at the division of 639450 by 45 
We're looking to find how many times 45 goes into 639450.

Let's proceed to step 1:
45 can be fit into 6 0 times, resulting in a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Bring next digit (3) of the dividend behind the 6 and repeat the process: 63 / 45

On to step 2:
The number 45 fits into 63 1 times, leaving a remainder of 18.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtracting 45 from 63 leaves us with 18.
Grab the next digit (9) from the dividend, add it to 18, then carry on: 189 / 45

Moving on to step 3:
The number 45 fits into 189 4 times, leaving a remainder of 9.
Write down 4 as next digit of the result. 
Result so far: 14.0
Deduct 180 from 189 and we're left with 9.
Take the next digit (4) from the dividend and append it to 9, then repeat: 94 / 45

Going ahead to step 4:
The number 45 fits into 94 2 times, leaving a remainder of 4.
Record the quotient 2 as the next digit in the result. 
Result so far: 142.0
Subtracting 90 from 94 leaves us with 4.
Take the next digit (5) from the dividend and append it to 4, then repeat: 45 / 45

Going ahead to step 5:
If we divide 45 by 45, we get 1 and a remainder of 0.
The number 1 becomes the next digit in our result. 
Result so far: 1421.0
If we subtract 45 from 45, we get 0.
Fetch the next digit (0) from the dividend, attach it to 0 and continue: 0 / 45

On to step 6:
0 divided by 45 is 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 14210.0
Subtracting 0 from 0 leaves us with 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 7:
0 divided by 45 is 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 14210.0
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 8:
45 goes into 0 0 times with a remainder of 0.
The next digit of our result is 0. 
Result so far: 14210.0
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 result is 14210.0 with a remainder of 0.0.