803521 divided by 80 
We want to divide 803521 by 80.

Advancing to step 1:
8 divided by 80 is 0 with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Append the next digit (0) from the dividend to 8 and continue with: 80 / 80

Moving on to step 2:
The number 80 fits into 80 1 times, leaving a remainder of 0.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Subtract 80 from 80 to get 0.
Include the next digit (3) from the dividend after 0, then repeat: 3 / 80

On to step 3:
When dividing 3 by 80, we get 0 with a remainder of 3.
The next digit of our result is 0. 
Result so far: 10.0
Deduct 0 from 3 and we're left with 3.
Grab the next digit (5) from the dividend, add it to 3, then carry on: 35 / 80

Advancing to step 4:
When dividing 35 by 80, we get 0 with a remainder of 35.
The number 0 becomes the next digit in our result. 
Result so far: 100.0
The remainder is 35 after subtracting 0 from 35.
Append the next digit (2) from the dividend to 35 and continue with: 352 / 80

Going ahead to step 5:
352 divided by 80 is 4 with a remainder of 32.
Record the quotient 4 as the next digit in the result. 
Result so far: 1004.0
If we subtract 320 from 352, we get 32.
Take the next digit (1) from the dividend and append it to 32, then repeat: 321 / 80

Going ahead to step 6:
321 divided by 80 is 4 with a remainder of 1.
The number 4 becomes the next digit in our result. 
Result so far: 10044.0
The remainder is 1 after subtracting 320 from 321.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Step 7:
80 goes into 10 0 times with a remainder of 10.
Write down 0 as next digit of the result. 
Result so far: 10044.0
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 8:
When dividing 100 by 80, we get 1 with a remainder of 20.
Put 1 as the next digit of the answer. 
Result so far: 10044.01
If we take 80 away from 100, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 9:
When dividing 200 by 80, we get 2 with a remainder of 40.
The number 2 becomes the next digit in our result. 
Result so far: 10044.012
The remainder is 40 after subtracting 160 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Step 10:
80 goes into 400 5 times with a remainder of 0.
The number 5 becomes the next digit in our result. 
Result so far: 10044.0125
Deduct 400 from 400 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 11:
When dividing 0 by 80, we get 0 with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 10044.0125
If we take 0 away from 0, we end up with 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 12:
When dividing 0 by 80, we get 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 10044.0125
The remainder is 0 after subtracting 0 from 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 10044.0125 with a remainder of 0.0.