We're dividing 603950 by 91 
The aim is to understand the frequency of 91 in 603950.

Advancing to step 1:
The number 91 fits into 6 0 times, leaving a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Bring next digit (0) of the dividend behind the 6 and repeat the process: 60 / 91

Advancing to step 2:
When dividing 60 by 91, we get 0 with a remainder of 60.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 60, we end up with 60.
Bring next digit (3) of the dividend behind the 60 and repeat the process: 603 / 91

Advancing to step 3:
603 divided by 91 is 6 with a remainder of 57.
Write down 6 as next digit of the result. 
Result so far: 6.0
Deduct 546 from 603 and we're left with 57.
Take the next digit (9) from the dividend and append it to 57, then repeat: 579 / 91

Moving on to step 4:
91 goes into 579 6 times with a remainder of 33.
The next digit of our result is 6. 
Result so far: 66.0
The remainder is 33 after subtracting 546 from 579.
Append the next digit (5) from the dividend to 33 and continue with: 335 / 91

Moving on to step 5:
335 divided by 91 is 3 with a remainder of 62.
Record the quotient 3 as the next digit in the result. 
Result so far: 663.0
Subtract 273 from 335 to get 62.
Grab the next digit (0) from the dividend, add it to 62, then carry on: 620 / 91

Step 6:
When dividing 620 by 91, we get 6 with a remainder of 74.
Write down 6 as next digit of the result. 
Result so far: 6636.0
Subtracting 546 from 620 leaves us with 74.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Advancing to step 7:
91 goes into 740 8 times with a remainder of 12.
The next digit of our result is 8. 
Result so far: 6636.8
Subtract 728 from 740 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 8:
The number 91 fits into 120 1 times, leaving a remainder of 29.
The next digit of our result is 1. 
Result so far: 6636.81
Subtract 91 from 120 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Let's proceed to step 9:
When dividing 290 by 91, we get 3 with a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 6636.813
Subtract 273 from 290 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 10:
91 can be fit into 170 1 times, resulting in a remainder of 79.
The next digit of our result is 1. 
Result so far: 6636.8131
Deduct 91 from 170 and we're left with 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

On to step 11:
When dividing 790 by 91, we get 8 with a remainder of 62.
Write down 8 as next digit of the result. 
Result so far: 6636.81318
If we subtract 728 from 790, we get 62.
Since there are no more digits in the dividend, we add a zero to the remainder making it 620, and continue the process.

Let's proceed to step 12:
91 can be fit into 620 6 times, resulting in a remainder of 74.
Put 6 as the next digit of the answer. 
Result so far: 6636.813186
The remainder is 74 after subtracting 546 from 620.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Moving on to step 13:
If we divide 740 by 91, we get 8 and a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 6636.8131868
Deduct 728 from 740 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 14:
120 divided by 91 is 1 with a remainder of 29.
The next digit of our result is 1. 
Result so far: 6636.81318681
If we take 91 away from 120, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

After the division, we end up with 6636.81318681 and a remainder of 2.9e-08.