143879 divided by 11 
The aim is to understand the frequency of 11 in 143879.

Moving on to step 1:
If we divide 1 by 11, we get 0 and a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Fetch the next digit (4) from the dividend, attach it to 1 and continue: 14 / 11

Going ahead to step 2:
11 goes into 14 1 times with a remainder of 3.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we take 11 away from 14, we end up with 3.
Bring next digit (3) of the dividend behind the 3 and repeat the process: 33 / 11

On to step 3:
11 goes into 33 3 times with a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 13.0
If we subtract 33 from 33, we get 0.
Take the next digit (8) from the dividend and append it to 0, then repeat: 8 / 11

Going ahead to step 4:
8 divided by 11 is 0 with a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 130.0
Subtracting 0 from 8 leaves us with 8.
Grab the next digit (7) from the dividend, add it to 8, then carry on: 87 / 11

Moving on to step 5:
If we divide 87 by 11, we get 7 and a remainder of 10.
The next digit of our result is 7. 
Result so far: 1307.0
Deduct 77 from 87 and we're left with 10.
Include the next digit (9) from the dividend after 10, then repeat: 109 / 11

Step 6:
11 can be fit into 109 9 times, resulting in a remainder of 10.
The next digit of our result is 9. 
Result so far: 13079.0
Subtract 99 from 109 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 7:
If we divide 100 by 11, we get 9 and a remainder of 1.
The number 9 becomes the next digit in our result. 
Result so far: 13079.9
Subtract 99 from 100 to 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.

On to step 8:
11 goes into 10 0 times with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 13079.9
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 9:
When dividing 100 by 11, we get 9 with a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 13079.909
Subtracting 99 from 100 leaves us 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 10:
11 can be fit into 10 0 times, resulting in a remainder of 10.
Write down 0 as next digit of the result. 
Result so far: 13079.909
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.

Moving on to step 11:
The number 11 fits into 100 9 times, leaving a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 13079.90909
If we subtract 99 from 100, 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.

Let's proceed to step 12:
The number 11 fits into 10 0 times, leaving a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 13079.90909
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 13:
11 goes into 100 9 times with a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 13079.9090909
If we subtract 99 from 100, 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.

On to step 14:
If we divide 10 by 11, we get 0 and a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 13079.9090909
If we subtract 0 from 10, we get 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 final result is 13079.9090909 with a remainder of 1e-08.