83701916 ÷ 646 
The aim is to understand the frequency of 646 in 83701916.

On to step 1:
8 divided by 646 is 0 with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Fetch the next digit (3) from the dividend, attach it to 8 and continue: 83 / 646

Advancing to step 2:
When dividing 83 by 646, we get 0 with a remainder of 83.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 83 to get 83.
Include the next digit (7) from the dividend after 83, then repeat: 837 / 646

Let's proceed to step 3:
646 goes into 837 1 times with a remainder of 191.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Deduct 646 from 837 and we're left with 191.
Bring next digit (0) of the dividend behind the 191 and repeat the process: 1910 / 646

Advancing to step 4:
1910 divided by 646 is 2 with a remainder of 618.
Record the quotient 2 as the next digit in the result. 
Result so far: 12.0
If we take 1292 away from 1910, we end up with 618.
Fetch the next digit (1) from the dividend, attach it to 618 and continue: 6181 / 646

Step 5:
646 can be fit into 6181 9 times, resulting in a remainder of 367.
Use 9 as the next digit of our solution. 
Result so far: 129.0
If we take 5814 away from 6181, we end up with 367.
Append the next digit (9) from the dividend to 367 and continue with: 3679 / 646

Advancing to step 6:
646 goes into 3679 5 times with a remainder of 449.
Write down 5 as next digit of the result. 
Result so far: 1295.0
Subtract 3230 from 3679 to get 449.
Take the next digit (1) from the dividend and append it to 449, then repeat: 4491 / 646

Going ahead to step 7:
646 can be fit into 4491 6 times, resulting in a remainder of 615.
Write down 6 as next digit of the result. 
Result so far: 12956.0
Subtract 3876 from 4491 to get 615.
Append the next digit (6) from the dividend to 615 and continue with: 6156 / 646

Let's proceed to step 8:
646 goes into 6156 9 times with a remainder of 342.
Record the quotient 9 as the next digit in the result. 
Result so far: 129569.0
If we take 5814 away from 6156, we end up with 342.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3420, and continue the process.

Advancing to step 9:
The number 646 fits into 3420 5 times, leaving a remainder of 190.
The next digit of our result is 5. 
Result so far: 129569.5
Subtract 3230 from 3420 to get 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

Going ahead to step 10:
646 goes into 1900 2 times with a remainder of 608.
Use 2 as the next digit of our solution. 
Result so far: 129569.52
Deduct 1292 from 1900 and we're left with 608.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6080, and continue the process.

Moving on to step 11:
The number 646 fits into 6080 9 times, leaving a remainder of 266.
Use 9 as the next digit of our solution. 
Result so far: 129569.529
The remainder is 266 after subtracting 5814 from 6080.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2660, and continue the process.

Going ahead to step 12:
646 goes into 2660 4 times with a remainder of 76.
Record the quotient 4 as the next digit in the result. 
Result so far: 129569.5294
Subtract 2584 from 2660 to get 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Let's proceed to step 13:
646 goes into 760 1 times with a remainder of 114.
Put 1 as the next digit of the answer. 
Result so far: 129569.52941
Subtracting 646 from 760 leaves us with 114.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1140, and continue the process.

Advancing to step 14:
646 goes into 1140 1 times with a remainder of 494.
Record the quotient 1 as the next digit in the result. 
Result so far: 129569.529411
Subtracting 646 from 1140 leaves us with 494.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4940, and continue the process.

The final result is 129569.529411 with a remainder of 4.94e-05.