We divide 516839 by 90
The aim is to understand the frequency of 90 in 516839.

Let's proceed to step 1:
90 goes into 5 0 times with a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 90

Let's proceed to step 2:
If we divide 51 by 90, we get 0 and a remainder of 51.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 51, we end up with 51.
Include the next digit (6) from the dividend after 51, then repeat: 516 / 90

On to step 3:
When dividing 516 by 90, we get 5 with a remainder of 66.
Write down 5 as next digit of the result. 
Result so far: 5.0
The remainder is 66 after subtracting 450 from 516.
Include the next digit (8) from the dividend after 66, then repeat: 668 / 90

Let's proceed to step 4:
90 can be fit into 668 7 times, resulting in a remainder of 38.
Record the quotient 7 as the next digit in the result. 
Result so far: 57.0
Deduct 630 from 668 and we're left with 38.
Fetch the next digit (3) from the dividend, attach it to 38 and continue: 383 / 90

Advancing to step 5:
383 divided by 90 is 4 with a remainder of 23.
The next digit of our result is 4. 
Result so far: 574.0
If we subtract 360 from 383, we get 23.
Fetch the next digit (9) from the dividend, attach it to 23 and continue: 239 / 90

Let's proceed to step 6:
If we divide 239 by 90, we get 2 and a remainder of 59.
Write down 2 as next digit of the result. 
Result so far: 5742.0
If we subtract 180 from 239, we get 59.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

Step 7:
The number 90 fits into 590 6 times, leaving a remainder of 50.
The next digit of our result is 6. 
Result so far: 5742.6
Subtracting 540 from 590 leaves us with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Moving on to step 8:
If we divide 500 by 90, we get 5 and a remainder of 50.
Put 5 as the next digit of the answer. 
Result so far: 5742.65
Subtracting 450 from 500 leaves us with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 9:
500 divided by 90 is 5 with a remainder of 50.
The next digit of our result is 5. 
Result so far: 5742.655
If we take 450 away from 500, we end up with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

The final result is 5742.655 with a remainder of 0.005.