We're dividing 165881 by 45 
The aim is to understand the frequency of 45 in 165881.

Step 1:
When dividing 1 by 45, we get 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Include the next digit (6) from the dividend after 1, then repeat: 16 / 45

Advancing to step 2:
45 goes into 16 0 times with a remainder of 16.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 16 and we're left with 16.
Bring next digit (5) of the dividend behind the 16 and repeat the process: 165 / 45

Let's proceed to step 3:
When dividing 165 by 45, we get 3 with a remainder of 30.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
The remainder is 30 after subtracting 135 from 165.
Take the next digit (8) from the dividend and append it to 30, then repeat: 308 / 45

Going ahead to step 4:
308 divided by 45 is 6 with a remainder of 38.
Write down 6 as next digit of the result. 
Result so far: 36.0
If we take 270 away from 308, we end up with 38.
Grab the next digit (8) from the dividend, add it to 38, then carry on: 388 / 45

Let's proceed to step 5:
When dividing 388 by 45, we get 8 with a remainder of 28.
Use 8 as the next digit of our solution. 
Result so far: 368.0
Deduct 360 from 388 and we're left with 28.
Bring next digit (1) of the dividend behind the 28 and repeat the process: 281 / 45

On to step 6:
If we divide 281 by 45, we get 6 and a remainder of 11.
Use 6 as the next digit of our solution. 
Result so far: 3686.0
The remainder is 11 after subtracting 270 from 281.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 7:
45 can be fit into 110 2 times, resulting in a remainder of 20.
Use 2 as the next digit of our solution. 
Result so far: 3686.2
Subtract 90 from 110 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 8:
200 divided by 45 is 4 with a remainder of 20.
Record the quotient 4 as the next digit in the result. 
Result so far: 3686.24
The remainder is 20 after subtracting 180 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 9:
45 can be fit into 200 4 times, resulting in a remainder of 20.
The number 4 becomes the next digit in our result. 
Result so far: 3686.244
Subtract 180 from 200 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final outcome is 3686.244, with a leftover of 0.002.