We're dividing 99903021 by 977 
We want to divide 99903021 by 977.

Step 1:
977 can be fit into 9 0 times, resulting in a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 9, we end up with 9.
Take the next digit (9) from the dividend and append it to 9, then repeat: 99 / 977

On to step 2:
If we divide 99 by 977, we get 0 and a remainder of 99.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 99 leaves us with 99.
Append the next digit (9) from the dividend to 99 and continue with: 999 / 977

Going ahead to step 3:
977 goes into 999 1 times with a remainder of 22.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 977 away from 999, we end up with 22.
Include the next digit (0) from the dividend after 22, then repeat: 220 / 977

Step 4:
220 divided by 977 is 0 with a remainder of 220.
Use 0 as the next digit of our solution. 
Result so far: 10.0
Deduct 0 from 220 and we're left with 220.
Take the next digit (3) from the dividend and append it to 220, then repeat: 2203 / 977

Step 5:
If we divide 2203 by 977, we get 2 and a remainder of 249.
The number 2 becomes the next digit in our result. 
Result so far: 102.0
If we take 1954 away from 2203, we end up with 249.
Fetch the next digit (0) from the dividend, attach it to 249 and continue: 2490 / 977

Let's proceed to step 6:
The number 977 fits into 2490 2 times, leaving a remainder of 536.
The next digit of our result is 2. 
Result so far: 1022.0
Deduct 1954 from 2490 and we're left with 536.
Bring next digit (2) of the dividend behind the 536 and repeat the process: 5362 / 977

Let's proceed to step 7:
977 goes into 5362 5 times with a remainder of 477.
Use 5 as the next digit of our solution. 
Result so far: 10225.0
Subtract 4885 from 5362 to get 477.
Fetch the next digit (1) from the dividend, attach it to 477 and continue: 4771 / 977

Let's proceed to step 8:
4771 divided by 977 is 4 with a remainder of 863.
Use 4 as the next digit of our solution. 
Result so far: 102254.0
Subtract 3908 from 4771 to get 863.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8630, and continue the process.

Advancing to step 9:
977 goes into 8630 8 times with a remainder of 814.
The next digit of our result is 8. 
Result so far: 102254.8
If we subtract 7816 from 8630, we get 814.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8140, and continue the process.

Step 10:
8140 divided by 977 is 8 with a remainder of 324.
Write down 8 as next digit of the result. 
Result so far: 102254.88
Subtract 7816 from 8140 to get 324.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3240, and continue the process.

The final outcome is 102254.88, with a leftover of 0.324.