We divide 260290 by 12
We want to figure out the number of times 260290 can be divided by 12.

Going ahead to step 1:
2 divided by 12 is 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Fetch the next digit (6) from the dividend, attach it to 2 and continue: 26 / 12

On to step 2:
When dividing 26 by 12, we get 2 with a remainder of 2.
The next digit of our result is 2. 
Result so far: 2.0
Subtract 24 from 26 to get 2.
Include the next digit (0) from the dividend after 2, then repeat: 20 / 12

Advancing to step 3:
If we divide 20 by 12, we get 1 and a remainder of 8.
Record the quotient 1 as the next digit in the result. 
Result so far: 21.0
Subtract 12 from 20 to get 8.
Include the next digit (2) from the dividend after 8, then repeat: 82 / 12

On to step 4:
12 goes into 82 6 times with a remainder of 10.
The number 6 becomes the next digit in our result. 
Result so far: 216.0
If we subtract 72 from 82, we get 10.
Take the next digit (9) from the dividend and append it to 10, then repeat: 109 / 12

Step 5:
12 goes into 109 9 times with a remainder of 1.
The next digit of our result is 9. 
Result so far: 2169.0
If we take 108 away from 109, we end up with 1.
Take the next digit (0) from the dividend and append it to 1, then repeat: 10 / 12

Going ahead to step 6:
When dividing 10 by 12, we get 0 with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 21690.0
If we take 0 away from 10, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 7:
The number 12 fits into 100 8 times, leaving a remainder of 4.
Put 8 as the next digit of the answer. 
Result so far: 21690.8
Deduct 96 from 100 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.

Let's proceed to step 8:
12 goes into 40 3 times with a remainder of 4.
Write down 3 as next digit of the result. 
Result so far: 21690.83
If we subtract 36 from 40, we 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.

On to step 9:
40 divided by 12 is 3 with a remainder of 4.
Use 3 as the next digit of our solution. 
Result so far: 21690.833
The remainder is 4 after subtracting 36 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

The final outcome is 21690.833, with a leftover of 0.0004.