663623 divided by 45 
The aim is to understand the frequency of 45 in 663623.

Step 1:
6 divided by 45 is 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Fetch the next digit (6) from the dividend, attach it to 6 and continue: 66 / 45

Step 2:
45 goes into 66 1 times with a remainder of 21.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 21 after subtracting 45 from 66.
Fetch the next digit (3) from the dividend, attach it to 21 and continue: 213 / 45

Step 3:
The number 45 fits into 213 4 times, leaving a remainder of 33.
Put 4 as the next digit of the answer. 
Result so far: 14.0
If we take 180 away from 213, we end up with 33.
Fetch the next digit (6) from the dividend, attach it to 33 and continue: 336 / 45

On to step 4:
45 goes into 336 7 times with a remainder of 21.
Use 7 as the next digit of our solution. 
Result so far: 147.0
If we take 315 away from 336, we end up with 21.
Bring next digit (2) of the dividend behind the 21 and repeat the process: 212 / 45

Step 5:
45 goes into 212 4 times with a remainder of 32.
The next digit of our result is 4. 
Result so far: 1474.0
If we subtract 180 from 212, we get 32.
Append the next digit (3) from the dividend to 32 and continue with: 323 / 45

Going ahead to step 6:
323 divided by 45 is 7 with a remainder of 8.
The next digit of our result is 7. 
Result so far: 14747.0
The remainder is 8 after subtracting 315 from 323.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 7:
If we divide 80 by 45, we get 1 and a remainder of 35.
Write down 1 as next digit of the result. 
Result so far: 14747.1
Subtracting 45 from 80 leaves us with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Let's proceed to step 8:
350 divided by 45 is 7 with a remainder of 35.
Record the quotient 7 as the next digit in the result. 
Result so far: 14747.17
Subtracting 315 from 350 leaves us with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Step 9:
The number 45 fits into 350 7 times, leaving a remainder of 35.
Write down 7 as next digit of the result. 
Result so far: 14747.177
Subtracting 315 from 350 leaves us with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

After the division, we end up with 14747.177 and a remainder of 0.0035.