312438 ÷ 78 
Our goal is to divide 312438 by 78.

Moving on to step 1:
If we divide 3 by 78, we get 0 and a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Grab the next digit (1) from the dividend, add it to 3, then carry on: 31 / 78

Going ahead to step 2:
The number 78 fits into 31 0 times, leaving a remainder of 31.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 31 to get 31.
Take the next digit (2) from the dividend and append it to 31, then repeat: 312 / 78

On to step 3:
The number 78 fits into 312 4 times, leaving a remainder of 0.
The next digit of our result is 4. 
Result so far: 4.0
The remainder is 0 after subtracting 312 from 312.
Fetch the next digit (4) from the dividend, attach it to 0 and continue: 4 / 78

Step 4:
When dividing 4 by 78, we get 0 with a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 40.0
Subtracting 0 from 4 leaves us with 4.
Bring next digit (3) of the dividend behind the 4 and repeat the process: 43 / 78

Advancing to step 5:
43 divided by 78 is 0 with a remainder of 43.
Use 0 as the next digit of our solution. 
Result so far: 400.0
Subtracting 0 from 43 leaves us with 43.
Fetch the next digit (8) from the dividend, attach it to 43 and continue: 438 / 78

On to step 6:
78 goes into 438 5 times with a remainder of 48.
The number 5 becomes the next digit in our result. 
Result so far: 4005.0
If we subtract 390 from 438, we get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Moving on to step 7:
78 goes into 480 6 times with a remainder of 12.
Put 6 as the next digit of the answer. 
Result so far: 4005.6
Deduct 468 from 480 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 8:
If we divide 120 by 78, we get 1 and a remainder of 42.
Put 1 as the next digit of the answer. 
Result so far: 4005.61
If we subtract 78 from 120, we get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Step 9:
When dividing 420 by 78, we get 5 with a remainder of 30.
Put 5 as the next digit of the answer. 
Result so far: 4005.615
The remainder is 30 after subtracting 390 from 420.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

On to step 10:
The number 78 fits into 300 3 times, leaving a remainder of 66.
The next digit of our result is 3. 
Result so far: 4005.6153
If we subtract 234 from 300, we get 66.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

Moving on to step 11:
The number 78 fits into 660 8 times, leaving a remainder of 36.
The number 8 becomes the next digit in our result. 
Result so far: 4005.61538
The remainder is 36 after subtracting 624 from 660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Going ahead to step 12:
78 goes into 360 4 times with a remainder of 48.
Put 4 as the next digit of the answer. 
Result so far: 4005.615384
Subtract 312 from 360 to get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Advancing to step 13:
78 can be fit into 480 6 times, resulting in a remainder of 12.
The next digit of our result is 6. 
Result so far: 4005.6153846
If we take 468 away from 480, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 14:
If we divide 120 by 78, we get 1 and a remainder of 42.
The number 1 becomes the next digit in our result. 
Result so far: 4005.61538461
Subtract 78 from 120 to get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

The quotient of the division is 4005.61538461, and the remainder is 4.2e-08.