We look at the division of 300438 by 90 
The aim is to understand the frequency of 90 in 300438.

Let's proceed to step 1:
If we divide 3 by 90, we get 0 and a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Include the next digit (0) from the dividend after 3, then repeat: 30 / 90

On to step 2:
If we divide 30 by 90, we get 0 and a remainder of 30.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 30 leaves us with 30.
Grab the next digit (0) from the dividend, add it to 30, then carry on: 300 / 90

On to step 3:
If we divide 300 by 90, we get 3 and a remainder of 30.
Write down 3 as next digit of the result. 
Result so far: 3.0
Subtracting 270 from 300 leaves us with 30.
Fetch the next digit (4) from the dividend, attach it to 30 and continue: 304 / 90

Going ahead to step 4:
90 goes into 304 3 times with a remainder of 34.
Put 3 as the next digit of the answer. 
Result so far: 33.0
Subtracting 270 from 304 leaves us with 34.
Bring next digit (3) of the dividend behind the 34 and repeat the process: 343 / 90

Going ahead to step 5:
90 goes into 343 3 times with a remainder of 73.
Write down 3 as next digit of the result. 
Result so far: 333.0
Deduct 270 from 343 and we're left with 73.
Fetch the next digit (8) from the dividend, attach it to 73 and continue: 738 / 90

Step 6:
90 can be fit into 738 8 times, resulting in a remainder of 18.
Record the quotient 8 as the next digit in the result. 
Result so far: 3338.0
If we take 720 away from 738, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 7:
180 divided by 90 is 2 with a remainder of 0.
Put 2 as the next digit of the answer. 
Result so far: 3338.2
Subtract 180 from 180 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
0 divided by 90 is 0 with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 3338.2
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 9:
90 goes into 0 0 times with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 3338.2
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

In conclusion, the division gives 3338.2 with a balance of 0.0.