We're dividing 386851 by 78 
We want to divide 386851 by 78.

Step 1:
78 goes into 3 0 times with a remainder of 3.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Grab the next digit (8) from the dividend, add it to 3, then carry on: 38 / 78

Moving on to step 2:
78 can be fit into 38 0 times, resulting in a remainder of 38.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 38, we end up with 38.
Take the next digit (6) from the dividend and append it to 38, then repeat: 386 / 78

Going ahead to step 3:
78 goes into 386 4 times with a remainder of 74.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
Deduct 312 from 386 and we're left with 74.
Bring next digit (8) of the dividend behind the 74 and repeat the process: 748 / 78

Moving on to step 4:
78 can be fit into 748 9 times, resulting in a remainder of 46.
Write down 9 as next digit of the result. 
Result so far: 49.0
If we subtract 702 from 748, we get 46.
Fetch the next digit (5) from the dividend, attach it to 46 and continue: 465 / 78

Moving on to step 5:
The number 78 fits into 465 5 times, leaving a remainder of 75.
Record the quotient 5 as the next digit in the result. 
Result so far: 495.0
Deduct 390 from 465 and we're left with 75.
Append the next digit (1) from the dividend to 75 and continue with: 751 / 78

Moving on to step 6:
78 goes into 751 9 times with a remainder of 49.
Put 9 as the next digit of the answer. 
Result so far: 4959.0
Deduct 702 from 751 and we're left with 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Step 7:
If we divide 490 by 78, we get 6 and a remainder of 22.
Put 6 as the next digit of the answer. 
Result so far: 4959.6
Deduct 468 from 490 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Moving on to step 8:
If we divide 220 by 78, we get 2 and a remainder of 64.
The next digit of our result is 2. 
Result so far: 4959.62
Deduct 156 from 220 and we're left with 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Step 9:
If we divide 640 by 78, we get 8 and a remainder of 16.
Use 8 as the next digit of our solution. 
Result so far: 4959.628
Subtracting 624 from 640 leaves us with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 10:
78 goes into 160 2 times with a remainder of 4.
The next digit of our result is 2. 
Result so far: 4959.6282
Subtracting 156 from 160 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 11:
78 goes into 40 0 times with a remainder of 40.
Use 0 as the next digit of our solution. 
Result so far: 4959.6282
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Let's proceed to step 12:
The number 78 fits into 400 5 times, leaving a remainder of 10.
Record the quotient 5 as the next digit in the result. 
Result so far: 4959.628205
If we subtract 390 from 400, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 13:
100 divided by 78 is 1 with a remainder of 22.
The next digit of our result is 1. 
Result so far: 4959.6282051
Subtract 78 from 100 to get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Advancing to step 14:
78 can be fit into 220 2 times, resulting in a remainder of 64.
The next digit of our result is 2. 
Result so far: 4959.62820512
If we subtract 156 from 220, we get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

The final result is 4959.62820512 with a remainder of 6.4e-08.