We look at the division of 887920 by 13 
The aim is to understand the frequency of 13 in 887920.

Going ahead to step 1:
When dividing 8 by 13, we get 0 with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Fetch the next digit (8) from the dividend, attach it to 8 and continue: 88 / 13

On to step 2:
13 can be fit into 88 6 times, resulting in a remainder of 10.
Record the quotient 6 as the next digit in the result. 
Result so far: 6.0
The remainder is 10 after subtracting 78 from 88.
Include the next digit (7) from the dividend after 10, then repeat: 107 / 13

Going ahead to step 3:
The number 13 fits into 107 8 times, leaving a remainder of 3.
Record the quotient 8 as the next digit in the result. 
Result so far: 68.0
Deduct 104 from 107 and we're left with 3.
Take the next digit (9) from the dividend and append it to 3, then repeat: 39 / 13

Going ahead to step 4:
13 goes into 39 3 times with a remainder of 0.
Record the quotient 3 as the next digit in the result. 
Result so far: 683.0
Subtracting 39 from 39 leaves us with 0.
Grab the next digit (2) from the dividend, add it to 0, then carry on: 2 / 13

On to step 5:
2 divided by 13 is 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 6830.0
If we subtract 0 from 2, we get 2.
Append the next digit (0) from the dividend to 2 and continue with: 20 / 13

Let's proceed to step 6:
The number 13 fits into 20 1 times, leaving a remainder of 7.
Use 1 as the next digit of our solution. 
Result so far: 68301.0
If we subtract 13 from 20, we 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.

Advancing to step 7:
The number 13 fits into 70 5 times, leaving a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 68301.5
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.

Moving on to step 8:
13 goes into 50 3 times with a remainder of 11.
The next digit of our result is 3. 
Result so far: 68301.53
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.

Going ahead to step 9:
The number 13 fits into 110 8 times, leaving a remainder of 6.
Record the quotient 8 as the next digit in the result. 
Result so far: 68301.538
The remainder is 6 after subtracting 104 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Let's proceed to step 10:
13 can be fit into 60 4 times, resulting in a remainder of 8.
The number 4 becomes the next digit in our result. 
Result so far: 68301.5384
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.

Advancing to step 11:
When dividing 80 by 13, we get 6 with a remainder of 2.
Put 6 as the next digit of the answer. 
Result so far: 68301.53846
If we take 78 away from 80, we end up 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 12:
20 divided by 13 is 1 with a remainder of 7.
Record the quotient 1 as the next digit in the result. 
Result so far: 68301.538461
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.

Step 13:
If we divide 70 by 13, we get 5 and a remainder of 5.
The number 5 becomes the next digit in our result. 
Result so far: 68301.5384615
Subtract 65 from 70 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.

Advancing to step 14:
13 can be fit into 50 3 times, resulting in a remainder of 11.
Put 3 as the next digit of the answer. 
Result so far: 68301.53846153
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.

The final result is 68301.53846153 with a remainder of 1.1e-08.