We look at the division of 9189610 by 408 
The aim is to understand the frequency of 408 in 9189610.

On to step 1:
If we divide 9 by 408, we get 0 and a remainder of 9.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 9 to get 9.
Grab the next digit (1) from the dividend, add it to 9, then carry on: 91 / 408

Moving on to step 2:
408 goes into 91 0 times with a remainder of 91.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 91, we end up with 91.
Take the next digit (8) from the dividend and append it to 91, then repeat: 918 / 408

Going ahead to step 3:
918 divided by 408 is 2 with a remainder of 102.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Subtracting 816 from 918 leaves us with 102.
Include the next digit (9) from the dividend after 102, then repeat: 1029 / 408

On to step 4:
If we divide 1029 by 408, we get 2 and a remainder of 213.
The next digit of our result is 2. 
Result so far: 22.0
If we subtract 816 from 1029, we get 213.
Append the next digit (6) from the dividend to 213 and continue with: 2136 / 408

Going ahead to step 5:
408 goes into 2136 5 times with a remainder of 96.
The next digit of our result is 5. 
Result so far: 225.0
If we subtract 2040 from 2136, we get 96.
Include the next digit (1) from the dividend after 96, then repeat: 961 / 408

Let's proceed to step 6:
When dividing 961 by 408, we get 2 with a remainder of 145.
Use 2 as the next digit of our solution. 
Result so far: 2252.0
Deduct 816 from 961 and we're left with 145.
Take the next digit (0) from the dividend and append it to 145, then repeat: 1450 / 408

Moving on to step 7:
1450 divided by 408 is 3 with a remainder of 226.
Write down 3 as next digit of the result. 
Result so far: 22523.0
Subtract 1224 from 1450 to get 226.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2260, and continue the process.

Advancing to step 8:
408 can be fit into 2260 5 times, resulting in a remainder of 220.
Write down 5 as next digit of the result. 
Result so far: 22523.5
If we take 2040 away from 2260, we end up with 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Let's proceed to step 9:
408 can be fit into 2200 5 times, resulting in a remainder of 160.
Put 5 as the next digit of the answer. 
Result so far: 22523.55
Subtracting 2040 from 2200 leaves us with 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

The final outcome is 22523.55, with a leftover of 0.16.