12951760 ÷ 669 
We want to figure out the number of times 12951760 can be divided by 669.

Let's proceed to step 1:
If we divide 1 by 669, we get 0 and a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Include the next digit (2) from the dividend after 1, then repeat: 12 / 669

Step 2:
669 can be fit into 12 0 times, resulting in a remainder of 12.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 12 to get 12.
Take the next digit (9) from the dividend and append it to 12, then repeat: 129 / 669

Advancing to step 3:
669 can be fit into 129 0 times, resulting in a remainder of 129.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 129, we get 129.
Fetch the next digit (5) from the dividend, attach it to 129 and continue: 1295 / 669

On to step 4:
If we divide 1295 by 669, we get 1 and a remainder of 626.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Deduct 669 from 1295 and we're left with 626.
Include the next digit (1) from the dividend after 626, then repeat: 6261 / 669

Step 5:
When dividing 6261 by 669, we get 9 with a remainder of 240.
Write down 9 as next digit of the result. 
Result so far: 19.0
If we take 6021 away from 6261, we end up with 240.
Bring next digit (7) of the dividend behind the 240 and repeat the process: 2407 / 669

Moving on to step 6:
The number 669 fits into 2407 3 times, leaving a remainder of 400.
Use 3 as the next digit of our solution. 
Result so far: 193.0
If we take 2007 away from 2407, we end up with 400.
Grab the next digit (6) from the dividend, add it to 400, then carry on: 4006 / 669

Step 7:
The number 669 fits into 4006 5 times, leaving a remainder of 661.
Record the quotient 5 as the next digit in the result. 
Result so far: 1935.0
Deduct 3345 from 4006 and we're left with 661.
Append the next digit (0) from the dividend to 661 and continue with: 6610 / 669

Step 8:
When dividing 6610 by 669, we get 9 with a remainder of 589.
Record the quotient 9 as the next digit in the result. 
Result so far: 19359.0
If we take 6021 away from 6610, we end up with 589.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5890, and continue the process.

On to step 9:
669 can be fit into 5890 8 times, resulting in a remainder of 538.
Record the quotient 8 as the next digit in the result. 
Result so far: 19359.8
Deduct 5352 from 5890 and we're left with 538.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5380, and continue the process.

Let's proceed to step 10:
The number 669 fits into 5380 8 times, leaving a remainder of 28.
The next digit of our result is 8. 
Result so far: 19359.88
The remainder is 28 after subtracting 5352 from 5380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

The final outcome is 19359.88, with a leftover of 0.028.