398905 ÷ 45 
The aim is to understand the frequency of 45 in 398905.

Step 1:
45 goes into 3 0 times with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Grab the next digit (9) from the dividend, add it to 3, then carry on: 39 / 45

Moving on to step 2:
The number 45 fits into 39 0 times, leaving a remainder of 39.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 39 and we're left with 39.
Bring next digit (8) of the dividend behind the 39 and repeat the process: 398 / 45

Going ahead to step 3:
The number 45 fits into 398 8 times, leaving a remainder of 38.
Use 8 as the next digit of our solution. 
Result so far: 8.0
Deduct 360 from 398 and we're left with 38.
Append the next digit (9) from the dividend to 38 and continue with: 389 / 45

Moving on to step 4:
When dividing 389 by 45, we get 8 with a remainder of 29.
Use 8 as the next digit of our solution. 
Result so far: 88.0
The remainder is 29 after subtracting 360 from 389.
Bring next digit (0) of the dividend behind the 29 and repeat the process: 290 / 45

Advancing to step 5:
When dividing 290 by 45, we get 6 with a remainder of 20.
The number 6 becomes the next digit in our result. 
Result so far: 886.0
Deduct 270 from 290 and we're left with 20.
Bring next digit (5) of the dividend behind the 20 and repeat the process: 205 / 45

On to step 6:
If we divide 205 by 45, we get 4 and a remainder of 25.
The next digit of our result is 4. 
Result so far: 8864.0
Deduct 180 from 205 and we're left 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.

Going ahead to step 7:
45 goes into 250 5 times with a remainder of 25.
Put 5 as the next digit of the answer. 
Result so far: 8864.5
If we subtract 225 from 250, we get 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Advancing to step 8:
If we divide 250 by 45, we get 5 and a remainder of 25.
Put 5 as the next digit of the answer. 
Result so far: 8864.55
Deduct 225 from 250 and we're left 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 result is 8864.55 with a remainder of 0.025.