We look at the division of 449891 by 45 
The aim is to understand the frequency of 45 in 449891.

Moving on to step 1:
When dividing 4 by 45, we get 0 with a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 4, we get 4.
Take the next digit (4) from the dividend and append it to 4, then repeat: 44 / 45

Step 2:
45 can be fit into 44 0 times, resulting in a remainder of 44.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 44, we get 44.
Bring next digit (9) of the dividend behind the 44 and repeat the process: 449 / 45

On to step 3:
The number 45 fits into 449 9 times, leaving a remainder of 44.
Put 9 as the next digit of the answer. 
Result so far: 9.0
The remainder is 44 after subtracting 405 from 449.
Grab the next digit (8) from the dividend, add it to 44, then carry on: 448 / 45

Step 4:
When dividing 448 by 45, we get 9 with a remainder of 43.
Put 9 as the next digit of the answer. 
Result so far: 99.0
Deduct 405 from 448 and we're left with 43.
Take the next digit (9) from the dividend and append it to 43, then repeat: 439 / 45

Advancing to step 5:
439 divided by 45 is 9 with a remainder of 34.
Use 9 as the next digit of our solution. 
Result so far: 999.0
Subtract 405 from 439 to get 34.
Take the next digit (1) from the dividend and append it to 34, then repeat: 341 / 45

Going ahead to step 6:
If we divide 341 by 45, we get 7 and a remainder of 26.
Use 7 as the next digit of our solution. 
Result so far: 9997.0
Deduct 315 from 341 and we're left with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 7:
If we divide 260 by 45, we get 5 and a remainder of 35.
Put 5 as the next digit of the answer. 
Result so far: 9997.5
Deduct 225 from 260 and we're left 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 8:
350 divided by 45 is 7 with a remainder of 35.
The next digit of our result is 7. 
Result so far: 9997.57
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.

Let's proceed to step 9:
350 divided by 45 is 7 with a remainder of 35.
Write down 7 as next digit of the result. 
Result so far: 9997.577
If we subtract 315 from 350, we get 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

The final outcome is 9997.577, with a leftover of 0.0035.