We're dividing 513621 by 13 
The aim is to understand the frequency of 13 in 513621.

On to step 1:
13 goes into 5 0 times with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 13

Step 2:
If we divide 51 by 13, we get 3 and a remainder of 12.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Subtract 39 from 51 to get 12.
Include the next digit (3) from the dividend after 12, then repeat: 123 / 13

Moving on to step 3:
123 divided by 13 is 9 with a remainder of 6.
The number 9 becomes the next digit in our result. 
Result so far: 39.0
Subtract 117 from 123 to get 6.
Bring next digit (6) of the dividend behind the 6 and repeat the process: 66 / 13

Step 4:
66 divided by 13 is 5 with a remainder of 1.
The number 5 becomes the next digit in our result. 
Result so far: 395.0
If we take 65 away from 66, we end up with 1.
Include the next digit (2) from the dividend after 1, then repeat: 12 / 13

Moving on to step 5:
The number 13 fits into 12 0 times, leaving a remainder of 12.
Use 0 as the next digit of our solution. 
Result so far: 3950.0
Subtracting 0 from 12 leaves us with 12.
Include the next digit (1) from the dividend after 12, then repeat: 121 / 13

Advancing to step 6:
13 can be fit into 121 9 times, resulting in a remainder of 4.
The number 9 becomes the next digit in our result. 
Result so far: 39509.0
The remainder is 4 after subtracting 117 from 121.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 7:
40 divided by 13 is 3 with a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 39509.3
If we subtract 39 from 40, we get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Step 8:
13 goes into 10 0 times with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 39509.3
The remainder is 10 after subtracting 0 from 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 9:
13 can be fit into 100 7 times, resulting in a remainder of 9.
Write down 7 as next digit of the result. 
Result so far: 39509.307
Subtracting 91 from 100 leaves us with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Moving on to step 10:
90 divided by 13 is 6 with a remainder of 12.
Put 6 as the next digit of the answer. 
Result so far: 39509.3076
If we subtract 78 from 90, we 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.

Step 11:
120 divided by 13 is 9 with a remainder of 3.
Use 9 as the next digit of our solution. 
Result so far: 39509.30769
If we subtract 117 from 120, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 12:
13 goes into 30 2 times with a remainder of 4.
The next digit of our result is 2. 
Result so far: 39509.307692
If we subtract 26 from 30, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 13:
When dividing 40 by 13, we get 3 with a remainder of 1.
Write down 3 as next digit of the result. 
Result so far: 39509.3076923
The remainder is 1 after subtracting 39 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Let's proceed to step 14:
If we divide 10 by 13, we get 0 and a remainder of 10.
Write down 0 as next digit of the result. 
Result so far: 39509.3076923
Subtracting 0 from 10 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The quotient of the division is 39509.3076923, and the remainder is 1e-08.