We look at the division of 135121 by 9 
Our goal is to divide 135121 by 9.

Step 1:
9 goes into 1 0 times with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 9

Step 2:
13 divided by 9 is 1 with a remainder of 4.
Use 1 as the next digit of our solution. 
Result so far: 1.0
If we take 9 away from 13, we end up with 4.
Grab the next digit (5) from the dividend, add it to 4, then carry on: 45 / 9

Advancing to step 3:
9 goes into 45 5 times with a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 15.0
If we subtract 45 from 45, we get 0.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 9

Advancing to step 4:
9 goes into 1 0 times with a remainder of 1.
The next digit of our result is 0. 
Result so far: 150.0
The remainder is 1 after subtracting 0 from 1.
Append the next digit (2) from the dividend to 1 and continue with: 12 / 9

Moving on to step 5:
The number 9 fits into 12 1 times, leaving a remainder of 3.
Record the quotient 1 as the next digit in the result. 
Result so far: 1501.0
If we take 9 away from 12, we end up with 3.
Take the next digit (1) from the dividend and append it to 3, then repeat: 31 / 9

On to step 6:
When dividing 31 by 9, we get 3 with a remainder of 4.
Use 3 as the next digit of our solution. 
Result so far: 15013.0
The remainder is 4 after subtracting 27 from 31.
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:
The number 9 fits into 40 4 times, leaving a remainder of 4.
Put 4 as the next digit of the answer. 
Result so far: 15013.4
Deduct 36 from 40 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

On to step 8:
9 goes into 40 4 times with a remainder of 4.
Use 4 as the next digit of our solution. 
Result so far: 15013.44
Subtracting 36 from 40 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Our division results in 15013.44 with a remaining 0.004.