129446 ÷ 12 
We want to figure out the number of times 129446 can be divided by 12.

Advancing to step 1:
12 goes into 1 0 times with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 12

Going ahead to step 2:
12 goes into 12 1 times with a remainder of 0.
The next digit of our result is 1. 
Result so far: 1.0
Subtracting 12 from 12 leaves us with 0.
Include the next digit (9) from the dividend after 0, then repeat: 9 / 12

Step 3:
If we divide 9 by 12, we get 0 and a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 10.0
Deduct 0 from 9 and we're left with 9.
Append the next digit (4) from the dividend to 9 and continue with: 94 / 12

Step 4:
The number 12 fits into 94 7 times, leaving a remainder of 10.
Record the quotient 7 as the next digit in the result. 
Result so far: 107.0
The remainder is 10 after subtracting 84 from 94.
Include the next digit (4) from the dividend after 10, then repeat: 104 / 12

Step 5:
If we divide 104 by 12, we get 8 and a remainder of 8.
Record the quotient 8 as the next digit in the result. 
Result so far: 1078.0
Deduct 96 from 104 and we're left with 8.
Grab the next digit (6) from the dividend, add it to 8, then carry on: 86 / 12

Step 6:
86 divided by 12 is 7 with a remainder of 2.
The next digit of our result is 7. 
Result so far: 10787.0
Subtracting 84 from 86 leaves us 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.

On to step 7:
12 can be fit into 20 1 times, resulting in a remainder of 8.
The next digit of our result is 1. 
Result so far: 10787.1
Subtract 12 from 20 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.

Step 8:
12 can be fit into 80 6 times, resulting in a remainder of 8.
Put 6 as the next digit of the answer. 
Result so far: 10787.16
If we subtract 72 from 80, we 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.

On to step 9:
12 can be fit into 80 6 times, resulting in a remainder of 8.
Record the quotient 6 as the next digit in the result. 
Result so far: 10787.166
Subtracting 72 from 80 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Our division results in 10787.166 with a remaining 0.0008.