We look at the division of 381783 by 39 
The aim is to understand the frequency of 39 in 381783.

Step 1:
When dividing 3 by 39, we get 0 with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Append the next digit (8) from the dividend to 3 and continue with: 38 / 39

On to step 2:
39 goes into 38 0 times with a remainder of 38.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 38 and we're left with 38.
Append the next digit (1) from the dividend to 38 and continue with: 381 / 39

Advancing to step 3:
The number 39 fits into 381 9 times, leaving a remainder of 30.
Write down 9 as next digit of the result. 
Result so far: 9.0
Deduct 351 from 381 and we're left with 30.
Include the next digit (7) from the dividend after 30, then repeat: 307 / 39

Step 4:
307 divided by 39 is 7 with a remainder of 34.
Write down 7 as next digit of the result. 
Result so far: 97.0
Subtracting 273 from 307 leaves us with 34.
Append the next digit (8) from the dividend to 34 and continue with: 348 / 39

Let's proceed to step 5:
The number 39 fits into 348 8 times, leaving a remainder of 36.
The next digit of our result is 8. 
Result so far: 978.0
Deduct 312 from 348 and we're left with 36.
Fetch the next digit (3) from the dividend, attach it to 36 and continue: 363 / 39

On to step 6:
The number 39 fits into 363 9 times, leaving a remainder of 12.
Use 9 as the next digit of our solution. 
Result so far: 9789.0
Deduct 351 from 363 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Advancing to step 7:
The number 39 fits into 120 3 times, leaving a remainder of 3.
Record the quotient 3 as the next digit in the result. 
Result so far: 9789.3
If we take 117 away from 120, we end up 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.

Going ahead to step 8:
30 divided by 39 is 0 with a remainder of 30.
The number 0 becomes the next digit in our result. 
Result so far: 9789.3
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.

Step 9:
If we divide 300 by 39, we get 7 and a remainder of 27.
Record the quotient 7 as the next digit in the result. 
Result so far: 9789.307
Deduct 273 from 300 and we're left with 27.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

Step 10:
When dividing 270 by 39, we get 6 with a remainder of 36.
The next digit of our result is 6. 
Result so far: 9789.3076
Subtract 234 from 270 to get 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Advancing to step 11:
If we divide 360 by 39, we get 9 and a remainder of 9.
The next digit of our result is 9. 
Result so far: 9789.30769
Subtract 351 from 360 to get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

On to step 12:
The number 39 fits into 90 2 times, leaving a remainder of 12.
Put 2 as the next digit of the answer. 
Result so far: 9789.307692
Subtracting 78 from 90 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 13:
120 divided by 39 is 3 with a remainder of 3.
Write down 3 as next digit of the result. 
Result so far: 9789.3076923
If we subtract 117 from 120, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 14:
When dividing 30 by 39, we get 0 with a remainder of 30.
Write down 0 as next digit of the result. 
Result so far: 9789.3076923
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.

After the division, we end up with 9789.3076923 and a remainder of 3e-08.