We look at the division of 870936 by 31 
The aim is to understand the frequency of 31 in 870936.

Advancing to step 1:
If we divide 8 by 31, we get 0 and a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Bring next digit (7) of the dividend behind the 8 and repeat the process: 87 / 31

Moving on to step 2:
When dividing 87 by 31, we get 2 with a remainder of 25.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
The remainder is 25 after subtracting 62 from 87.
Bring next digit (0) of the dividend behind the 25 and repeat the process: 250 / 31

Going ahead to step 3:
When dividing 250 by 31, we get 8 with a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 28.0
Subtracting 248 from 250 leaves us with 2.
Take the next digit (9) from the dividend and append it to 2, then repeat: 29 / 31

Moving on to step 4:
When dividing 29 by 31, we get 0 with a remainder of 29.
Use 0 as the next digit of our solution. 
Result so far: 280.0
If we take 0 away from 29, we end up with 29.
Append the next digit (3) from the dividend to 29 and continue with: 293 / 31

Moving on to step 5:
If we divide 293 by 31, we get 9 and a remainder of 14.
Put 9 as the next digit of the answer. 
Result so far: 2809.0
Subtract 279 from 293 to get 14.
Grab the next digit (6) from the dividend, add it to 14, then carry on: 146 / 31

Step 6:
If we divide 146 by 31, we get 4 and a remainder of 22.
Write down 4 as next digit of the result. 
Result so far: 28094.0
If we subtract 124 from 146, we get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Let's proceed to step 7:
31 can be fit into 220 7 times, resulting in a remainder of 3.
Write down 7 as next digit of the result. 
Result so far: 28094.7
Deduct 217 from 220 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Moving on to step 8:
31 can be fit into 30 0 times, resulting in a remainder of 30.
The next digit of our result is 0. 
Result so far: 28094.7
If we take 0 away from 30, we end up with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

On to step 9:
If we divide 300 by 31, we get 9 and a remainder of 21.
The next digit of our result is 9. 
Result so far: 28094.709
Deduct 279 from 300 and we're left with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Going ahead to step 10:
31 can be fit into 210 6 times, resulting in a remainder of 24.
The next digit of our result is 6. 
Result so far: 28094.7096
Subtract 186 from 210 to get 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Moving on to step 11:
240 divided by 31 is 7 with a remainder of 23.
The number 7 becomes the next digit in our result. 
Result so far: 28094.70967
The remainder is 23 after subtracting 217 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Moving on to step 12:
The number 31 fits into 230 7 times, leaving a remainder of 13.
Use 7 as the next digit of our solution. 
Result so far: 28094.709677
Subtract 217 from 230 to get 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

In conclusion, the division gives 28094.709677 with a balance of 1.3e-06.