12940288 ÷ 991 
We're looking to find how many times 991 goes into 12940288.

Step 1:
1 divided by 991 is 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 991

Going ahead to step 2:
991 can be fit into 12 0 times, resulting in a remainder of 12.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 12 after subtracting 0 from 12.
Bring next digit (9) of the dividend behind the 12 and repeat the process: 129 / 991

Let's proceed to step 3:
If we divide 129 by 991, we get 0 and a remainder of 129.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 129 and we're left with 129.
Grab the next digit (4) from the dividend, add it to 129, then carry on: 1294 / 991

Step 4:
When dividing 1294 by 991, we get 1 with a remainder of 303.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtract 991 from 1294 to get 303.
Include the next digit (0) from the dividend after 303, then repeat: 3030 / 991

Going ahead to step 5:
991 can be fit into 3030 3 times, resulting in a remainder of 57.
Use 3 as the next digit of our solution. 
Result so far: 13.0
Subtract 2973 from 3030 to get 57.
Grab the next digit (2) from the dividend, add it to 57, then carry on: 572 / 991

Let's proceed to step 6:
If we divide 572 by 991, we get 0 and a remainder of 572.
Write down 0 as next digit of the result. 
Result so far: 130.0
If we take 0 away from 572, we end up with 572.
Include the next digit (8) from the dividend after 572, then repeat: 5728 / 991

Moving on to step 7:
If we divide 5728 by 991, we get 5 and a remainder of 773.
The next digit of our result is 5. 
Result so far: 1305.0
Deduct 4955 from 5728 and we're left with 773.
Grab the next digit (8) from the dividend, add it to 773, then carry on: 7738 / 991

Moving on to step 8:
991 goes into 7738 7 times with a remainder of 801.
The next digit of our result is 7. 
Result so far: 13057.0
If we take 6937 away from 7738, we end up with 801.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8010, and continue the process.

Moving on to step 9:
8010 divided by 991 is 8 with a remainder of 82.
Put 8 as the next digit of the answer. 
Result so far: 13057.8
Subtracting 7928 from 8010 leaves us with 82.
Since there are no more digits in the dividend, we add a zero to the remainder making it 820, and continue the process.

Let's proceed to step 10:
When dividing 820 by 991, we get 0 with a remainder of 820.
Record the quotient 0 as the next digit in the result. 
Result so far: 13057.8
Subtracting 0 from 820 leaves us with 820.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8200, and continue the process.

Let's proceed to step 11:
991 goes into 8200 8 times with a remainder of 272.
The number 8 becomes the next digit in our result. 
Result so far: 13057.808
Subtracting 7928 from 8200 leaves us with 272.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2720, and continue the process.

Going ahead to step 12:
If we divide 2720 by 991, we get 2 and a remainder of 738.
Put 2 as the next digit of the answer. 
Result so far: 13057.8082
Deduct 1982 from 2720 and we're left with 738.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7380, and continue the process.

Going ahead to step 13:
991 goes into 7380 7 times with a remainder of 443.
The number 7 becomes the next digit in our result. 
Result so far: 13057.80827
Subtracting 6937 from 7380 leaves us with 443.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4430, and continue the process.

Moving on to step 14:
991 can be fit into 4430 4 times, resulting in a remainder of 466.
Write down 4 as next digit of the result. 
Result so far: 13057.808274
The remainder is 466 after subtracting 3964 from 4430.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4660, and continue the process.

Let's proceed to step 15:
If we divide 4660 by 991, we get 4 and a remainder of 696.
Use 4 as the next digit of our solution. 
Result so far: 13057.8082744
If we subtract 3964 from 4660, we get 696.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6960, and continue the process.

The final outcome is 13057.8082744, with a leftover of 6.96e-06.