Let's divide 309877 by 77
We're looking to find how many times 77 goes into 309877.

Step 1:
3 divided by 77 is 0 with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Fetch the next digit (0) from the dividend, attach it to 3 and continue: 30 / 77

On to step 2:
77 goes into 30 0 times with a remainder of 30.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 30, we end up with 30.
Append the next digit (9) from the dividend to 30 and continue with: 309 / 77

Going ahead to step 3:
77 can be fit into 309 4 times, resulting in a remainder of 1.
Use 4 as the next digit of our solution. 
Result so far: 4.0
If we take 308 away from 309, we end up with 1.
Take the next digit (8) from the dividend and append it to 1, then repeat: 18 / 77

On to step 4:
If we divide 18 by 77, we get 0 and a remainder of 18.
The number 0 becomes the next digit in our result. 
Result so far: 40.0
Deduct 0 from 18 and we're left with 18.
Fetch the next digit (7) from the dividend, attach it to 18 and continue: 187 / 77

Moving on to step 5:
If we divide 187 by 77, we get 2 and a remainder of 33.
Use 2 as the next digit of our solution. 
Result so far: 402.0
If we subtract 154 from 187, we get 33.
Append the next digit (7) from the dividend to 33 and continue with: 337 / 77

Step 6:
77 can be fit into 337 4 times, resulting in a remainder of 29.
Put 4 as the next digit of the answer. 
Result so far: 4024.0
Deduct 308 from 337 and we're left with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Going ahead to step 7:
The number 77 fits into 290 3 times, leaving a remainder of 59.
Put 3 as the next digit of the answer. 
Result so far: 4024.3
Subtracting 231 from 290 leaves us 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.

Advancing to step 8:
When dividing 590 by 77, we get 7 with a remainder of 51.
The next digit of our result is 7. 
Result so far: 4024.37
Subtracting 539 from 590 leaves us with 51.
Since there are no more digits in the dividend, we add a zero to the remainder making it 510, and continue the process.

Moving on to step 9:
510 divided by 77 is 6 with a remainder of 48.
Write down 6 as next digit of the result. 
Result so far: 4024.376
Subtract 462 from 510 to get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Moving on to step 10:
When dividing 480 by 77, we get 6 with a remainder of 18.
The number 6 becomes the next digit in our result. 
Result so far: 4024.3766
If we take 462 away from 480, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

The final outcome is 4024.3766, with a leftover of 0.00018.