80581515 ÷ 12 
Let's see how many times 12 fits into 80581515.

Going ahead to step 1:
12 goes into 8 0 times with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Bring next digit (0) of the dividend behind the 8 and repeat the process: 80 / 12

Step 2:
12 can be fit into 80 6 times, resulting in a remainder of 8.
Write down 6 as next digit of the result. 
Result so far: 6.0
If we take 72 away from 80, we end up with 8.
Take the next digit (5) from the dividend and append it to 8, then repeat: 85 / 12

Going ahead to step 3:
12 can be fit into 85 7 times, resulting in a remainder of 1.
Use 7 as the next digit of our solution. 
Result so far: 67.0
The remainder is 1 after subtracting 84 from 85.
Include the next digit (8) from the dividend after 1, then repeat: 18 / 12

Going ahead to step 4:
If we divide 18 by 12, we get 1 and a remainder of 6.
Record the quotient 1 as the next digit in the result. 
Result so far: 671.0
If we subtract 12 from 18, we get 6.
Take the next digit (1) from the dividend and append it to 6, then repeat: 61 / 12

Going ahead to step 5:
When dividing 61 by 12, we get 5 with a remainder of 1.
Record the quotient 5 as the next digit in the result. 
Result so far: 6715.0
Subtracting 60 from 61 leaves us with 1.
Append the next digit (5) from the dividend to 1 and continue with: 15 / 12

Advancing to step 6:
If we divide 15 by 12, we get 1 and a remainder of 3.
The next digit of our result is 1. 
Result so far: 67151.0
If we take 12 away from 15, we end up with 3.
Include the next digit (1) from the dividend after 3, then repeat: 31 / 12

Going ahead to step 7:
12 goes into 31 2 times with a remainder of 7.
Put 2 as the next digit of the answer. 
Result so far: 671512.0
If we subtract 24 from 31, we get 7.
Fetch the next digit (5) from the dividend, attach it to 7 and continue: 75 / 12

Moving on to step 8:
The number 12 fits into 75 6 times, leaving a remainder of 3.
Write down 6 as next digit of the result. 
Result so far: 6715126.0
Subtract 72 from 75 to get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Advancing to step 9:
If we divide 30 by 12, we get 2 and a remainder of 6.
Record the quotient 2 as the next digit in the result. 
Result so far: 6715126.2
If we take 24 away from 30, we end up with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 10:
When dividing 60 by 12, we get 5 with a remainder of 0.
The number 5 becomes the next digit in our result. 
Result so far: 6715126.25
If we take 60 away from 60, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 11:
When dividing 0 by 12, we get 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 6715126.25
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 12:
The number 12 fits into 0 0 times, leaving a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 6715126.25
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 6715126.25 with a remainder of 0.0.