691594 ÷ 90 
The aim is to understand the frequency of 90 in 691594.

Moving on to step 1:
When dividing 6 by 90, we get 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Fetch the next digit (9) from the dividend, attach it to 6 and continue: 69 / 90

On to step 2:
90 goes into 69 0 times with a remainder of 69.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 69 leaves us with 69.
Append the next digit (1) from the dividend to 69 and continue with: 691 / 90

On to step 3:
If we divide 691 by 90, we get 7 and a remainder of 61.
Write down 7 as next digit of the result. 
Result so far: 7.0
Subtracting 630 from 691 leaves us with 61.
Grab the next digit (5) from the dividend, add it to 61, then carry on: 615 / 90

On to step 4:
615 divided by 90 is 6 with a remainder of 75.
Record the quotient 6 as the next digit in the result. 
Result so far: 76.0
If we subtract 540 from 615, we get 75.
Take the next digit (9) from the dividend and append it to 75, then repeat: 759 / 90

Advancing to step 5:
The number 90 fits into 759 8 times, leaving a remainder of 39.
Put 8 as the next digit of the answer. 
Result so far: 768.0
If we take 720 away from 759, we end up with 39.
Grab the next digit (4) from the dividend, add it to 39, then carry on: 394 / 90

Advancing to step 6:
If we divide 394 by 90, we get 4 and a remainder of 34.
The number 4 becomes the next digit in our result. 
Result so far: 7684.0
Subtract 360 from 394 to get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Let's proceed to step 7:
90 can be fit into 340 3 times, resulting in a remainder of 70.
The number 3 becomes the next digit in our result. 
Result so far: 7684.3
Subtracting 270 from 340 leaves us with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Step 8:
The number 90 fits into 700 7 times, leaving a remainder of 70.
Put 7 as the next digit of the answer. 
Result so far: 7684.37
If we subtract 630 from 700, we get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Let's proceed to step 9:
When dividing 700 by 90, we get 7 with a remainder of 70.
Put 7 as the next digit of the answer. 
Result so far: 7684.377
Subtract 630 from 700 to get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

In conclusion, the division gives 7684.377 with a balance of 0.007.