13803999 ÷ 800 
The aim is to understand the frequency of 800 in 13803999.

Moving on to step 1:
800 can be fit into 1 0 times, resulting in a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 800

On to step 2:
800 goes into 13 0 times with a remainder of 13.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 13 to get 13.
Grab the next digit (8) from the dividend, add it to 13, then carry on: 138 / 800

Going ahead to step 3:
800 can be fit into 138 0 times, resulting in a remainder of 138.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 138, we end up with 138.
Include the next digit (0) from the dividend after 138, then repeat: 1380 / 800

Let's proceed to step 4:
800 goes into 1380 1 times with a remainder of 580.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 580 after subtracting 800 from 1380.
Bring next digit (3) of the dividend behind the 580 and repeat the process: 5803 / 800

On to step 5:
If we divide 5803 by 800, we get 7 and a remainder of 203.
The number 7 becomes the next digit in our result. 
Result so far: 17.0
Deduct 5600 from 5803 and we're left with 203.
Fetch the next digit (9) from the dividend, attach it to 203 and continue: 2039 / 800

Let's proceed to step 6:
2039 divided by 800 is 2 with a remainder of 439.
The next digit of our result is 2. 
Result so far: 172.0
If we subtract 1600 from 2039, we get 439.
Include the next digit (9) from the dividend after 439, then repeat: 4399 / 800

Advancing to step 7:
800 can be fit into 4399 5 times, resulting in a remainder of 399.
Record the quotient 5 as the next digit in the result. 
Result so far: 1725.0
Deduct 4000 from 4399 and we're left with 399.
Grab the next digit (9) from the dividend, add it to 399, then carry on: 3999 / 800

Step 8:
The number 800 fits into 3999 4 times, leaving a remainder of 799.
Put 4 as the next digit of the answer. 
Result so far: 17254.0
Subtract 3200 from 3999 to get 799.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7990, and continue the process.

On to step 9:
The number 800 fits into 7990 9 times, leaving a remainder of 790.
Use 9 as the next digit of our solution. 
Result so far: 17254.9
Deduct 7200 from 7990 and we're left with 790.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7900, and continue the process.

Step 10:
When dividing 7900 by 800, we get 9 with a remainder of 700.
Write down 9 as next digit of the result. 
Result so far: 17254.99
Subtracting 7200 from 7900 leaves us with 700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7000, and continue the process.

The quotient of the division is 17254.99, and the remainder is 0.7.