We're dividing 638181 by 13 
The aim is to understand the frequency of 13 in 638181.

Moving on to step 1:
13 can be fit into 6 0 times, resulting in a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Take the next digit (3) from the dividend and append it to 6, then repeat: 63 / 13

Advancing to step 2:
If we divide 63 by 13, we get 4 and a remainder of 11.
Put 4 as the next digit of the answer. 
Result so far: 4.0
If we subtract 52 from 63, we get 11.
Fetch the next digit (8) from the dividend, attach it to 11 and continue: 118 / 13

Advancing to step 3:
When dividing 118 by 13, we get 9 with a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 49.0
If we take 117 away from 118, we end up with 1.
Append the next digit (1) from the dividend to 1 and continue with: 11 / 13

Step 4:
If we divide 11 by 13, we get 0 and a remainder of 11.
Record the quotient 0 as the next digit in the result. 
Result so far: 490.0
Subtracting 0 from 11 leaves us with 11.
Grab the next digit (8) from the dividend, add it to 11, then carry on: 118 / 13

On to step 5:
If we divide 118 by 13, we get 9 and a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 4909.0
If we take 117 away from 118, we end up with 1.
Grab the next digit (1) from the dividend, add it to 1, then carry on: 11 / 13

Let's proceed to step 6:
The number 13 fits into 11 0 times, leaving a remainder of 11.
The number 0 becomes the next digit in our result. 
Result so far: 49090.0
If we take 0 away from 11, 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.

Going ahead to step 7:
The number 13 fits into 110 8 times, leaving a remainder of 6.
Use 8 as the next digit of our solution. 
Result so far: 49090.8
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 8:
13 can be fit into 60 4 times, resulting in a remainder of 8.
Put 4 as the next digit of the answer. 
Result so far: 49090.84
If we subtract 52 from 60, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 9:
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: 49090.846
If we subtract 78 from 80, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 10:
The number 13 fits into 20 1 times, leaving a remainder of 7.
Put 1 as the next digit of the answer. 
Result so far: 49090.8461
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 11:
The number 13 fits into 70 5 times, leaving a remainder of 5.
The next digit of our result is 5. 
Result so far: 49090.84615
If we take 65 away from 70, we end up with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 12:
When dividing 50 by 13, we get 3 with a remainder of 11.
Write down 3 as next digit of the result. 
Result so far: 49090.846153
Subtracting 39 from 50 leaves us 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 13:
The number 13 fits into 110 8 times, leaving a remainder of 6.
Use 8 as the next digit of our solution. 
Result so far: 49090.8461538
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.

On to step 14:
When dividing 60 by 13, we get 4 with a remainder of 8.
Record the quotient 4 as the next digit in the result. 
Result so far: 49090.84615384
Subtract 52 from 60 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Our division results in 49090.84615384 with a remaining 8e-09.