We're dividing 571423 by 13 
The aim is to understand the frequency of 13 in 571423.

Step 1:
The number 13 fits into 5 0 times, leaving a remainder of 5.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Fetch the next digit (7) from the dividend, attach it to 5 and continue: 57 / 13

Step 2:
13 goes into 57 4 times with a remainder of 5.
Write down 4 as next digit of the result. 
Result so far: 4.0
The remainder is 5 after subtracting 52 from 57.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 13

Advancing to step 3:
When dividing 51 by 13, we get 3 with a remainder of 12.
The number 3 becomes the next digit in our result. 
Result so far: 43.0
Subtracting 39 from 51 leaves us with 12.
Include the next digit (4) from the dividend after 12, then repeat: 124 / 13

Step 4:
If we divide 124 by 13, we get 9 and a remainder of 7.
Use 9 as the next digit of our solution. 
Result so far: 439.0
If we subtract 117 from 124, we get 7.
Grab the next digit (2) from the dividend, add it to 7, then carry on: 72 / 13

Going ahead to step 5:
The number 13 fits into 72 5 times, leaving a remainder of 7.
Use 5 as the next digit of our solution. 
Result so far: 4395.0
Subtract 65 from 72 to get 7.
Grab the next digit (3) from the dividend, add it to 7, then carry on: 73 / 13

Going ahead to step 6:
73 divided by 13 is 5 with a remainder of 8.
Put 5 as the next digit of the answer. 
Result so far: 43955.0
Deduct 65 from 73 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.

Moving on to step 7:
13 can be fit into 80 6 times, resulting in a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 43955.6
Deduct 78 from 80 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 8:
20 divided by 13 is 1 with a remainder of 7.
Put 1 as the next digit of the answer. 
Result so far: 43955.61
If we take 13 away from 20, we end up 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 9:
13 can be fit into 70 5 times, resulting in a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 43955.615
If we subtract 65 from 70, we 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 10:
If we divide 50 by 13, we get 3 and a remainder of 11.
The number 3 becomes the next digit in our result. 
Result so far: 43955.6153
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 11:
110 divided by 13 is 8 with a remainder of 6.
The next digit of our result is 8. 
Result so far: 43955.61538
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.

Going ahead to step 12:
13 goes into 60 4 times with a remainder of 8.
Write down 4 as next digit of the result. 
Result so far: 43955.615384
Subtracting 52 from 60 leaves us 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.

Moving on to step 13:
The number 13 fits into 80 6 times, leaving a remainder of 2.
The next digit of our result is 6. 
Result so far: 43955.6153846
Deduct 78 from 80 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Going ahead to step 14:
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: 43955.61538461
Subtract 13 from 20 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

The final outcome is 43955.61538461, with a leftover of 7e-09.