We divide 1983640 by 391
The aim is to understand the frequency of 391 in 1983640.

On to step 1:
1 divided by 391 is 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 391

Advancing to step 2:
391 goes into 19 0 times with a remainder of 19.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 19 leaves us with 19.
Fetch the next digit (8) from the dividend, attach it to 19 and continue: 198 / 391

Let's proceed to step 3:
When dividing 198 by 391, we get 0 with a remainder of 198.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 198 and we're left with 198.
Append the next digit (3) from the dividend to 198 and continue with: 1983 / 391

Step 4:
When dividing 1983 by 391, we get 5 with a remainder of 28.
Put 5 as the next digit of the answer. 
Result so far: 5.0
If we take 1955 away from 1983, we end up with 28.
Append the next digit (6) from the dividend to 28 and continue with: 286 / 391

Going ahead to step 5:
When dividing 286 by 391, we get 0 with a remainder of 286.
Put 0 as the next digit of the answer. 
Result so far: 50.0
The remainder is 286 after subtracting 0 from 286.
Append the next digit (4) from the dividend to 286 and continue with: 2864 / 391

Step 6:
The number 391 fits into 2864 7 times, leaving a remainder of 127.
The next digit of our result is 7. 
Result so far: 507.0
The remainder is 127 after subtracting 2737 from 2864.
Take the next digit (0) from the dividend and append it to 127, then repeat: 1270 / 391

On to step 7:
The number 391 fits into 1270 3 times, leaving a remainder of 97.
The next digit of our result is 3. 
Result so far: 5073.0
Deduct 1173 from 1270 and we're left with 97.
Since there are no more digits in the dividend, we add a zero to the remainder making it 970, and continue the process.

Let's proceed to step 8:
970 divided by 391 is 2 with a remainder of 188.
Use 2 as the next digit of our solution. 
Result so far: 5073.2
If we take 782 away from 970, we end up with 188.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1880, and continue the process.

Step 9:
When dividing 1880 by 391, we get 4 with a remainder of 316.
The number 4 becomes the next digit in our result. 
Result so far: 5073.24
The remainder is 316 after subtracting 1564 from 1880.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3160, and continue the process.

Going ahead to step 10:
The number 391 fits into 3160 8 times, leaving a remainder of 32.
The number 8 becomes the next digit in our result. 
Result so far: 5073.248
Deduct 3128 from 3160 and we're left with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Moving on to step 11:
If we divide 320 by 391, we get 0 and a remainder of 320.
Write down 0 as next digit of the result. 
Result so far: 5073.248
Subtracting 0 from 320 leaves us with 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3200, and continue the process.

Step 12:
3200 divided by 391 is 8 with a remainder of 72.
The number 8 becomes the next digit in our result. 
Result so far: 5073.24808
Subtract 3128 from 3200 to get 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Advancing to step 13:
When dividing 720 by 391, we get 1 with a remainder of 329.
Write down 1 as next digit of the result. 
Result so far: 5073.248081
The remainder is 329 after subtracting 391 from 720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3290, and continue the process.

On to step 14:
If we divide 3290 by 391, we get 8 and a remainder of 162.
Write down 8 as next digit of the result. 
Result so far: 5073.2480818
The remainder is 162 after subtracting 3128 from 3290.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1620, and continue the process.

Advancing to step 15:
The number 391 fits into 1620 4 times, leaving a remainder of 56.
Use 4 as the next digit of our solution. 
Result so far: 5073.24808184
If we take 1564 away from 1620, we end up with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

In conclusion, the division gives 5073.24808184 with a balance of 5.6e-08.