31906829 ÷ 646 
The aim is to understand the frequency of 646 in 31906829.

Going ahead to step 1:
When dividing 3 by 646, we get 0 with a remainder of 3.
Use 0 as the next digit of our solution. 
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 / 646

Moving on to step 2:
31 divided by 646 is 0 with a remainder of 31.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 31 and we're left with 31.
Include the next digit (9) from the dividend after 31, then repeat: 319 / 646

Moving on to step 3:
319 divided by 646 is 0 with a remainder of 319.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 319 leaves us with 319.
Bring next digit (0) of the dividend behind the 319 and repeat the process: 3190 / 646

Advancing to step 4:
When dividing 3190 by 646, we get 4 with a remainder of 606.
Use 4 as the next digit of our solution. 
Result so far: 4.0
The remainder is 606 after subtracting 2584 from 3190.
Append the next digit (6) from the dividend to 606 and continue with: 6066 / 646

On to step 5:
The number 646 fits into 6066 9 times, leaving a remainder of 252.
The next digit of our result is 9. 
Result so far: 49.0
Subtracting 5814 from 6066 leaves us with 252.
Fetch the next digit (8) from the dividend, attach it to 252 and continue: 2528 / 646

Advancing to step 6:
646 goes into 2528 3 times with a remainder of 590.
The number 3 becomes the next digit in our result. 
Result so far: 493.0
The remainder is 590 after subtracting 1938 from 2528.
Fetch the next digit (2) from the dividend, attach it to 590 and continue: 5902 / 646

Step 7:
646 can be fit into 5902 9 times, resulting in a remainder of 88.
Write down 9 as next digit of the result. 
Result so far: 4939.0
Subtract 5814 from 5902 to get 88.
Fetch the next digit (9) from the dividend, attach it to 88 and continue: 889 / 646

Step 8:
889 divided by 646 is 1 with a remainder of 243.
The number 1 becomes the next digit in our result. 
Result so far: 49391.0
The remainder is 243 after subtracting 646 from 889.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2430, and continue the process.

On to step 9:
The number 646 fits into 2430 3 times, leaving a remainder of 492.
Record the quotient 3 as the next digit in the result. 
Result so far: 49391.3
Deduct 1938 from 2430 and we're left with 492.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4920, and continue the process.

Moving on to step 10:
When dividing 4920 by 646, we get 7 with a remainder of 398.
The next digit of our result is 7. 
Result so far: 49391.37
Subtracting 4522 from 4920 leaves us with 398.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3980, and continue the process.

Step 11:
When dividing 3980 by 646, we get 6 with a remainder of 104.
The number 6 becomes the next digit in our result. 
Result so far: 49391.376
Subtract 3876 from 3980 to get 104.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1040, and continue the process.

Advancing to step 12:
If we divide 1040 by 646, we get 1 and a remainder of 394.
Write down 1 as next digit of the result. 
Result so far: 49391.3761
If we take 646 away from 1040, we end up with 394.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3940, and continue the process.

Step 13:
646 goes into 3940 6 times with a remainder of 64.
Record the quotient 6 as the next digit in the result. 
Result so far: 49391.37616
The remainder is 64 after subtracting 3876 from 3940.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Moving on to step 14:
646 goes into 640 0 times with a remainder of 640.
Put 0 as the next digit of the answer. 
Result so far: 49391.37616
If we subtract 0 from 640, we get 640.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6400, and continue the process.

Step 15:
646 can be fit into 6400 9 times, resulting in a remainder of 586.
Record the quotient 9 as the next digit in the result. 
Result so far: 49391.3761609
If we take 5814 away from 6400, we end up with 586.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5860, and continue the process.

On to step 16:
When dividing 5860 by 646, we get 9 with a remainder of 46.
The next digit of our result is 9. 
Result so far: 49391.37616099
The remainder is 46 after subtracting 5814 from 5860.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

After the division, we end up with 49391.37616099 and a remainder of 4.6e-08.