31809973 ÷ 820 
The aim is to understand the frequency of 820 in 31809973.

Let's proceed to step 1:
3 divided by 820 is 0 with a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Take the next digit (1) from the dividend and append it to 3, then repeat: 31 / 820

Advancing to step 2:
820 goes into 31 0 times with a remainder of 31.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 31, we get 31.
Grab the next digit (8) from the dividend, add it to 31, then carry on: 318 / 820

Step 3:
820 goes into 318 0 times with a remainder of 318.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 318 leaves us with 318.
Grab the next digit (0) from the dividend, add it to 318, then carry on: 3180 / 820

Step 4:
820 can be fit into 3180 3 times, resulting in a remainder of 720.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Subtracting 2460 from 3180 leaves us with 720.
Include the next digit (9) from the dividend after 720, then repeat: 7209 / 820

Going ahead to step 5:
If we divide 7209 by 820, we get 8 and a remainder of 649.
Write down 8 as next digit of the result. 
Result so far: 38.0
If we take 6560 away from 7209, we end up with 649.
Include the next digit (9) from the dividend after 649, then repeat: 6499 / 820

Step 6:
6499 divided by 820 is 7 with a remainder of 759.
Record the quotient 7 as the next digit in the result. 
Result so far: 387.0
Subtracting 5740 from 6499 leaves us with 759.
Take the next digit (7) from the dividend and append it to 759, then repeat: 7597 / 820

Advancing to step 7:
820 can be fit into 7597 9 times, resulting in a remainder of 217.
The number 9 becomes the next digit in our result. 
Result so far: 3879.0
If we subtract 7380 from 7597, we get 217.
Include the next digit (3) from the dividend after 217, then repeat: 2173 / 820

Let's proceed to step 8:
820 can be fit into 2173 2 times, resulting in a remainder of 533.
Record the quotient 2 as the next digit in the result. 
Result so far: 38792.0
The remainder is 533 after subtracting 1640 from 2173.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5330, and continue the process.

Moving on to step 9:
5330 divided by 820 is 6 with a remainder of 410.
Record the quotient 6 as the next digit in the result. 
Result so far: 38792.6
The remainder is 410 after subtracting 4920 from 5330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4100, and continue the process.

Moving on to step 10:
If we divide 4100 by 820, we get 5 and a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 38792.65
Deduct 4100 from 4100 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.

On to step 11:
0 divided by 820 is 0 with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 38792.65
Subtracting 0 from 0 leaves us 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.

On to step 12:
820 goes into 0 0 times with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 38792.65
Subtracting 0 from 0 leaves us 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.

After the division, we end up with 38792.65 and a remainder of 0.0.