78639 ÷ 25 
We're looking to find how many times 25 goes into 78639.

Advancing to step 1:
The number 25 fits into 7 0 times, leaving 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.
Fetch the next digit (8) from the dividend, attach it to 7 and continue: 78 / 25

Going ahead to step 2:
25 goes into 78 3 times with a remainder of 3.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
If we subtract 75 from 78, we get 3.
Fetch the next digit (6) from the dividend, attach it to 3 and continue: 36 / 25

Advancing to step 3:
When dividing 36 by 25, we get 1 with a remainder of 11.
Put 1 as the next digit of the answer. 
Result so far: 31.0
Deduct 25 from 36 and we're left with 11.
Fetch the next digit (3) from the dividend, attach it to 11 and continue: 113 / 25

Going ahead to step 4:
25 can be fit into 113 4 times, resulting in a remainder of 13.
Use 4 as the next digit of our solution. 
Result so far: 314.0
Subtract 100 from 113 to get 13.
Include the next digit (9) from the dividend after 13, then repeat: 139 / 25

On to step 5:
25 can be fit into 139 5 times, resulting in a remainder of 14.
The number 5 becomes the next digit in our result. 
Result so far: 3145.0
Subtract 125 from 139 to get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 6:
140 divided by 25 is 5 with a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 3145.5
The remainder is 15 after subtracting 125 from 140.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 7:
The number 25 fits into 150 6 times, leaving a remainder of 0.
The next digit of our result is 6. 
Result so far: 3145.56
Subtract 150 from 150 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 8:
0 divided by 25 is 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 3145.56
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 9:
25 can be fit into 0 0 times, resulting in a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 3145.56
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 3145.56 with a remainder of 0.0.