Let's divide 78400978 by 455
We want to divide 78400978 by 455.

On to step 1:
7 divided by 455 is 0 with a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 7 and we're left with 7.
Take the next digit (8) from the dividend and append it to 7, then repeat: 78 / 455

On to step 2:
If we divide 78 by 455, we get 0 and a remainder of 78.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 78, we get 78.
Append the next digit (4) from the dividend to 78 and continue with: 784 / 455

On to step 3:
If we divide 784 by 455, we get 1 and a remainder of 329.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Deduct 455 from 784 and we're left with 329.
Append the next digit (0) from the dividend to 329 and continue with: 3290 / 455

Moving on to step 4:
3290 divided by 455 is 7 with a remainder of 105.
Use 7 as the next digit of our solution. 
Result so far: 17.0
The remainder is 105 after subtracting 3185 from 3290.
Include the next digit (0) from the dividend after 105, then repeat: 1050 / 455

Step 5:
455 can be fit into 1050 2 times, resulting in a remainder of 140.
Write down 2 as next digit of the result. 
Result so far: 172.0
The remainder is 140 after subtracting 910 from 1050.
Take the next digit (9) from the dividend and append it to 140, then repeat: 1409 / 455

Step 6:
455 can be fit into 1409 3 times, resulting in a remainder of 44.
The next digit of our result is 3. 
Result so far: 1723.0
Subtracting 1365 from 1409 leaves us with 44.
Include the next digit (7) from the dividend after 44, then repeat: 447 / 455

Step 7:
455 goes into 447 0 times with a remainder of 447.
Write down 0 as next digit of the result. 
Result so far: 17230.0
Deduct 0 from 447 and we're left with 447.
Fetch the next digit (8) from the dividend, attach it to 447 and continue: 4478 / 455

Going ahead to step 8:
When dividing 4478 by 455, we get 9 with a remainder of 383.
The number 9 becomes the next digit in our result. 
Result so far: 172309.0
Deduct 4095 from 4478 and we're left with 383.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3830, and continue the process.

Let's proceed to step 9:
The number 455 fits into 3830 8 times, leaving a remainder of 190.
Record the quotient 8 as the next digit in the result. 
Result so far: 172309.8
The remainder is 190 after subtracting 3640 from 3830.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

Moving on to step 10:
455 can be fit into 1900 4 times, resulting in a remainder of 80.
Use 4 as the next digit of our solution. 
Result so far: 172309.84
Deduct 1820 from 1900 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Moving on to step 11:
800 divided by 455 is 1 with a remainder of 345.
The next digit of our result is 1. 
Result so far: 172309.841
The remainder is 345 after subtracting 455 from 800.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3450, and continue the process.

Let's proceed to step 12:
455 goes into 3450 7 times with a remainder of 265.
Put 7 as the next digit of the answer. 
Result so far: 172309.8417
Deduct 3185 from 3450 and we're left with 265.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

Moving on to step 13:
2650 divided by 455 is 5 with a remainder of 375.
Put 5 as the next digit of the answer. 
Result so far: 172309.84175
If we subtract 2275 from 2650, we get 375.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3750, and continue the process.

Step 14:
The number 455 fits into 3750 8 times, leaving a remainder of 110.
Put 8 as the next digit of the answer. 
Result so far: 172309.841758
Subtract 3640 from 3750 to get 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

Advancing to step 15:
1100 divided by 455 is 2 with a remainder of 190.
Write down 2 as next digit of the result. 
Result so far: 172309.8417582
Subtract 910 from 1100 to get 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

Step 16:
455 can be fit into 1900 4 times, resulting in a remainder of 80.
Use 4 as the next digit of our solution. 
Result so far: 172309.84175824
If we take 1820 away from 1900, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

The quotient of the division is 172309.84175824, and the remainder is 8e-08.