We divide 78720 by 77
We want to figure out the number of times 78720 can be divided by 77.

Step 1:
77 can be fit into 7 0 times, resulting in a remainder of 7.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 7 leaves us with 7.
Take the next digit (8) from the dividend and append it to 7, then repeat: 78 / 77

On to step 2:
The number 77 fits into 78 1 times, leaving a remainder of 1.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 1 after subtracting 77 from 78.
Grab the next digit (7) from the dividend, add it to 1, then carry on: 17 / 77

Advancing to step 3:
The number 77 fits into 17 0 times, leaving a remainder of 17.
Write down 0 as next digit of the result. 
Result so far: 10.0
Subtract 0 from 17 to get 17.
Take the next digit (2) from the dividend and append it to 17, then repeat: 172 / 77

Step 4:
If we divide 172 by 77, we get 2 and a remainder of 18.
Put 2 as the next digit of the answer. 
Result so far: 102.0
If we subtract 154 from 172, we get 18.
Take the next digit (0) from the dividend and append it to 18, then repeat: 180 / 77

Going ahead to step 5:
If we divide 180 by 77, we get 2 and a remainder of 26.
Write down 2 as next digit of the result. 
Result so far: 1022.0
Subtract 154 from 180 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 6:
77 goes into 260 3 times with a remainder of 29.
Put 3 as the next digit of the answer. 
Result so far: 1022.3
If we subtract 231 from 260, we get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Let's proceed to step 7:
77 goes into 290 3 times with a remainder of 59.
Put 3 as the next digit of the answer. 
Result so far: 1022.33
Deduct 231 from 290 and we're left with 59.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

The final outcome is 1022.33, with a leftover of 0.059.