We look at the division of 260523 by 90 
The aim is to understand the frequency of 90 in 260523.

Step 1:
90 can be fit into 2 0 times, resulting in a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Take the next digit (6) from the dividend and append it to 2, then repeat: 26 / 90

Let's proceed to step 2:
26 divided by 90 is 0 with a remainder of 26.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 26, we get 26.
Append the next digit (0) from the dividend to 26 and continue with: 260 / 90

Going ahead to step 3:
90 goes into 260 2 times with a remainder of 80.
Use 2 as the next digit of our solution. 
Result so far: 2.0
The remainder is 80 after subtracting 180 from 260.
Fetch the next digit (5) from the dividend, attach it to 80 and continue: 805 / 90

Let's proceed to step 4:
When dividing 805 by 90, we get 8 with a remainder of 85.
The next digit of our result is 8. 
Result so far: 28.0
Deduct 720 from 805 and we're left with 85.
Take the next digit (2) from the dividend and append it to 85, then repeat: 852 / 90

Going ahead to step 5:
90 goes into 852 9 times with a remainder of 42.
Use 9 as the next digit of our solution. 
Result so far: 289.0
Subtract 810 from 852 to get 42.
Fetch the next digit (3) from the dividend, attach it to 42 and continue: 423 / 90

Going ahead to step 6:
90 can be fit into 423 4 times, resulting in a remainder of 63.
Use 4 as the next digit of our solution. 
Result so far: 2894.0
Deduct 360 from 423 and we're left with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Step 7:
90 can be fit into 630 7 times, resulting in a remainder of 0.
Use 7 as the next digit of our solution. 
Result so far: 2894.7
Deduct 630 from 630 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 8:
90 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 2894.7
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 9:
0 divided by 90 is 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 2894.7
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.

The final result is 2894.7 with a remainder of 0.0.