661516 divided by 45 
The aim is to understand the frequency of 45 in 661516.

Going ahead 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
Deduct 0 from 6 and we're left with 6.
Bring next digit (6) of the dividend behind the 6 and repeat the process: 66 / 45

Advancing to step 2:
66 divided by 45 is 1 with a remainder of 21.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtract 45 from 66 to get 21.
Fetch the next digit (1) from the dividend, attach it to 21 and continue: 211 / 45

On to step 3:
211 divided by 45 is 4 with a remainder of 31.
Write down 4 as next digit of the result. 
Result so far: 14.0
Subtracting 180 from 211 leaves us with 31.
Append the next digit (5) from the dividend to 31 and continue with: 315 / 45

Going ahead to step 4:
315 divided by 45 is 7 with a remainder of 0.
Write down 7 as next digit of the result. 
Result so far: 147.0
The remainder is 0 after subtracting 315 from 315.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 45

On to step 5:
When dividing 1 by 45, we get 0 with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 1470.0
Subtracting 0 from 1 leaves us with 1.
Include the next digit (6) from the dividend after 1, then repeat: 16 / 45

Let's proceed to step 6:
16 divided by 45 is 0 with a remainder of 16.
Put 0 as the next digit of the answer. 
Result so far: 14700.0
The remainder is 16 after subtracting 0 from 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 7:
When dividing 160 by 45, we get 3 with a remainder of 25.
Use 3 as the next digit of our solution. 
Result so far: 14700.3
If we take 135 away from 160, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Moving on to step 8:
45 goes into 250 5 times with a remainder of 25.
The next digit of our result is 5. 
Result so far: 14700.35
The remainder is 25 after subtracting 225 from 250.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Step 9:
45 goes into 250 5 times with a remainder of 25.
Write down 5 as next digit of the result. 
Result so far: 14700.355
If we take 225 away from 250, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

The final outcome is 14700.355, with a leftover of 0.0025.