We look at the division of 451840 by 9 
The aim is to understand the frequency of 9 in 451840.

Let's proceed to step 1:
4 divided by 9 is 0 with a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Include the next digit (5) from the dividend after 4, then repeat: 45 / 9

Advancing to step 2:
45 divided by 9 is 5 with a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 5.0
Subtracting 45 from 45 leaves us with 0.
Grab the next digit (1) from the dividend, add it to 0, then carry on: 1 / 9

Step 3:
If we divide 1 by 9, we get 0 and a remainder of 1.
The next digit of our result is 0. 
Result so far: 50.0
If we take 0 away from 1, we end up with 1.
Bring next digit (8) of the dividend behind the 1 and repeat the process: 18 / 9

Advancing to step 4:
When dividing 18 by 9, we get 2 with a remainder of 0.
Use 2 as the next digit of our solution. 
Result so far: 502.0
If we subtract 18 from 18, we get 0.
Bring next digit (4) of the dividend behind the 0 and repeat the process: 4 / 9

Let's proceed to step 5:
9 can be fit into 4 0 times, resulting in a remainder of 4.
The next digit of our result is 0. 
Result so far: 5020.0
Deduct 0 from 4 and we're left with 4.
Include the next digit (0) from the dividend after 4, then repeat: 40 / 9

Moving on to step 6:
9 can be fit into 40 4 times, resulting in a remainder of 4.
Write down 4 as next digit of the result. 
Result so far: 50204.0
If we take 36 away from 40, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 7:
9 can be fit into 40 4 times, resulting in a remainder of 4.
The number 4 becomes the next digit in our result. 
Result so far: 50204.4
Deduct 36 from 40 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 8:
9 can be fit into 40 4 times, resulting in a remainder of 4.
The next digit of our result is 4. 
Result so far: 50204.44
Subtracting 36 from 40 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

After the division, we end up with 50204.44 and a remainder of 0.004.