353661 divided by 13 
The aim is to understand the frequency of 13 in 353661.

Let's proceed to step 1:
13 can be fit into 3 0 times, resulting in a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Bring next digit (5) of the dividend behind the 3 and repeat the process: 35 / 13

Moving on to step 2:
35 divided by 13 is 2 with a remainder of 9.
Write down 2 as next digit of the result. 
Result so far: 2.0
If we take 26 away from 35, we end up with 9.
Fetch the next digit (3) from the dividend, attach it to 9 and continue: 93 / 13

Step 3:
93 divided by 13 is 7 with a remainder of 2.
The number 7 becomes the next digit in our result. 
Result so far: 27.0
Subtract 91 from 93 to get 2.
Grab the next digit (6) from the dividend, add it to 2, then carry on: 26 / 13

Going ahead to step 4:
The number 13 fits into 26 2 times, leaving a remainder of 0.
Record the quotient 2 as the next digit in the result. 
Result so far: 272.0
If we subtract 26 from 26, we get 0.
Append the next digit (6) from the dividend to 0 and continue with: 6 / 13

Going ahead to step 5:
6 divided by 13 is 0 with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 2720.0
If we subtract 0 from 6, we get 6.
Fetch the next digit (1) from the dividend, attach it to 6 and continue: 61 / 13

Moving on to step 6:
When dividing 61 by 13, we get 4 with a remainder of 9.
Use 4 as the next digit of our solution. 
Result so far: 27204.0
Subtracting 52 from 61 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 7:
If we divide 90 by 13, we get 6 and a remainder of 12.
The number 6 becomes the next digit in our result. 
Result so far: 27204.6
Subtract 78 from 90 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:
When dividing 120 by 13, we get 9 with a remainder of 3.
Use 9 as the next digit of our solution. 
Result so far: 27204.69
Subtracting 117 from 120 leaves us with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 9:
30 divided by 13 is 2 with a remainder of 4.
Write down 2 as next digit of the result. 
Result so far: 27204.692
Subtract 26 from 30 to 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.

Let's proceed to step 10:
If we divide 40 by 13, we get 3 and a remainder of 1.
Use 3 as the next digit of our solution. 
Result so far: 27204.6923
Deduct 39 from 40 and we're left with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Going ahead to step 11:
If we divide 10 by 13, we get 0 and a remainder of 10.
The next digit of our result is 0. 
Result so far: 27204.6923
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 12:
The number 13 fits into 100 7 times, leaving a remainder of 9.
Use 7 as the next digit of our solution. 
Result so far: 27204.692307
Deduct 91 from 100 and we're left 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.

On to step 13:
13 goes into 90 6 times with a remainder of 12.
Use 6 as the next digit of our solution. 
Result so far: 27204.6923076
Subtract 78 from 90 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.

Let's proceed to step 14:
13 can be fit into 120 9 times, resulting in a remainder of 3.
Record the quotient 9 as the next digit in the result. 
Result so far: 27204.69230769
Subtracting 117 from 120 leaves us with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Our division results in 27204.69230769 with a remaining 3e-09.