We look at the division of 350823 by 13 
The aim is to understand the frequency of 13 in 350823.

On to step 1:
13 goes into 3 0 times with 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.
Take the next digit (5) from the dividend and append it to 3, then repeat: 35 / 13

Moving on to step 2:
13 goes into 35 2 times with a remainder of 9.
Use 2 as the next digit of our solution. 
Result so far: 2.0
The remainder is 9 after subtracting 26 from 35.
Bring next digit (0) of the dividend behind the 9 and repeat the process: 90 / 13

Let's proceed to step 3:
When dividing 90 by 13, we get 6 with a remainder of 12.
Write down 6 as next digit of the result. 
Result so far: 26.0
If we subtract 78 from 90, we get 12.
Include the next digit (8) from the dividend after 12, then repeat: 128 / 13

Going ahead to step 4:
The number 13 fits into 128 9 times, leaving a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 269.0
If we subtract 117 from 128, we get 11.
Append the next digit (2) from the dividend to 11 and continue with: 112 / 13

Step 5:
The number 13 fits into 112 8 times, leaving a remainder of 8.
Put 8 as the next digit of the answer. 
Result so far: 2698.0
If we subtract 104 from 112, we get 8.
Fetch the next digit (3) from the dividend, attach it to 8 and continue: 83 / 13

Step 6:
If we divide 83 by 13, we get 6 and a remainder of 5.
The number 6 becomes the next digit in our result. 
Result so far: 26986.0
Subtract 78 from 83 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 7:
13 goes into 50 3 times with a remainder of 11.
The number 3 becomes the next digit in our result. 
Result so far: 26986.3
Deduct 39 from 50 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 8:
13 goes into 110 8 times with a remainder of 6.
The next digit of our result is 8. 
Result so far: 26986.38
Subtract 104 from 110 to get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 9:
When dividing 60 by 13, we get 4 with a remainder of 8.
Use 4 as the next digit of our solution. 
Result so far: 26986.384
Deduct 52 from 60 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 10:
80 divided by 13 is 6 with a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 26986.3846
The remainder is 2 after subtracting 78 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 11:
13 can be fit into 20 1 times, resulting in a remainder of 7.
The next digit of our result is 1. 
Result so far: 26986.38461
Deduct 13 from 20 and we're left with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 12:
If we divide 70 by 13, we get 5 and a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 26986.384615
The remainder is 5 after subtracting 65 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 13:
13 goes into 50 3 times with a remainder of 11.
The next digit of our result is 3. 
Result so far: 26986.3846153
If we take 39 away from 50, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 14:
13 goes into 110 8 times with a remainder of 6.
Write down 8 as next digit of the result. 
Result so far: 26986.38461538
Subtracting 104 from 110 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

The final result is 26986.38461538 with a remainder of 6e-09.