12878138 ÷ 742 
Let's see how many times 742 fits into 12878138.

Step 1:
742 goes into 1 0 times with a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 742

Advancing to step 2:
If we divide 12 by 742, we get 0 and a remainder of 12.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 12 and we're left with 12.
Fetch the next digit (8) from the dividend, attach it to 12 and continue: 128 / 742

Let's proceed to step 3:
128 divided by 742 is 0 with a remainder of 128.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 128 to get 128.
Include the next digit (7) from the dividend after 128, then repeat: 1287 / 742

Advancing to step 4:
742 goes into 1287 1 times with a remainder of 545.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we subtract 742 from 1287, we get 545.
Fetch the next digit (8) from the dividend, attach it to 545 and continue: 5458 / 742

Advancing to step 5:
If we divide 5458 by 742, we get 7 and a remainder of 264.
Write down 7 as next digit of the result. 
Result so far: 17.0
If we subtract 5194 from 5458, we get 264.
Take the next digit (1) from the dividend and append it to 264, then repeat: 2641 / 742

Going ahead to step 6:
742 goes into 2641 3 times with a remainder of 415.
Write down 3 as next digit of the result. 
Result so far: 173.0
If we subtract 2226 from 2641, we get 415.
Append the next digit (3) from the dividend to 415 and continue with: 4153 / 742

On to step 7:
742 goes into 4153 5 times with a remainder of 443.
Use 5 as the next digit of our solution. 
Result so far: 1735.0
Subtract 3710 from 4153 to get 443.
Append the next digit (8) from the dividend to 443 and continue with: 4438 / 742

On to step 8:
If we divide 4438 by 742, we get 5 and a remainder of 728.
Write down 5 as next digit of the result. 
Result so far: 17355.0
If we subtract 3710 from 4438, we get 728.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7280, and continue the process.

Moving on to step 9:
If we divide 7280 by 742, we get 9 and a remainder of 602.
Write down 9 as next digit of the result. 
Result so far: 17355.9
If we subtract 6678 from 7280, we get 602.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6020, and continue the process.

Going ahead to step 10:
When dividing 6020 by 742, we get 8 with a remainder of 84.
Put 8 as the next digit of the answer. 
Result so far: 17355.98
The remainder is 84 after subtracting 5936 from 6020.
Since there are no more digits in the dividend, we add a zero to the remainder making it 840, and continue the process.

Going ahead to step 11:
742 can be fit into 840 1 times, resulting in a remainder of 98.
The number 1 becomes the next digit in our result. 
Result so far: 17355.981
If we take 742 away from 840, we end up with 98.
Since there are no more digits in the dividend, we add a zero to the remainder making it 980, and continue the process.

Going ahead to step 12:
The number 742 fits into 980 1 times, leaving a remainder of 238.
Record the quotient 1 as the next digit in the result. 
Result so far: 17355.9811
If we take 742 away from 980, we end up with 238.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2380, and continue the process.

The final outcome is 17355.9811, with a leftover of 0.00238.