We're dividing 663867 by 78 
We want to figure out the number of times 663867 can be divided by 78.

Advancing to step 1:
If we divide 6 by 78, we get 0 and a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Append the next digit (6) from the dividend to 6 and continue with: 66 / 78

Advancing to step 2:
78 can be fit into 66 0 times, resulting in a remainder of 66.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 66 and we're left with 66.
Grab the next digit (3) from the dividend, add it to 66, then carry on: 663 / 78

Let's proceed to step 3:
When dividing 663 by 78, we get 8 with a remainder of 39.
Write down 8 as next digit of the result. 
Result so far: 8.0
Subtracting 624 from 663 leaves us with 39.
Include the next digit (8) from the dividend after 39, then repeat: 398 / 78

Let's proceed to step 4:
398 divided by 78 is 5 with a remainder of 8.
Use 5 as the next digit of our solution. 
Result so far: 85.0
The remainder is 8 after subtracting 390 from 398.
Take the next digit (6) from the dividend and append it to 8, then repeat: 86 / 78

Step 5:
If we divide 86 by 78, we get 1 and a remainder of 8.
Put 1 as the next digit of the answer. 
Result so far: 851.0
Subtracting 78 from 86 leaves us with 8.
Append the next digit (7) from the dividend to 8 and continue with: 87 / 78

Step 6:
78 goes into 87 1 times with a remainder of 9.
The next digit of our result is 1. 
Result so far: 8511.0
Deduct 78 from 87 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Advancing to step 7:
When dividing 90 by 78, we get 1 with a remainder of 12.
The next digit of our result is 1. 
Result so far: 8511.1
Deduct 78 from 90 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:
78 goes into 120 1 times with a remainder of 42.
Write down 1 as next digit of the result. 
Result so far: 8511.11
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 final result is 8511.11 with a remainder of 0.042.