Let's divide 428666 by 39
The aim is to understand the frequency of 39 in 428666.

On to step 1:
4 divided by 39 is 0 with a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Grab the next digit (2) from the dividend, add it to 4, then carry on: 42 / 39

On to step 2:
If we divide 42 by 39, we get 1 and a remainder of 3.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Deduct 39 from 42 and we're left with 3.
Grab the next digit (8) from the dividend, add it to 3, then carry on: 38 / 39

Moving on to step 3:
39 can be fit into 38 0 times, resulting in a remainder of 38.
Put 0 as the next digit of the answer. 
Result so far: 10.0
If we take 0 away from 38, we end up with 38.
Fetch the next digit (6) from the dividend, attach it to 38 and continue: 386 / 39

Going ahead to step 4:
When dividing 386 by 39, we get 9 with a remainder of 35.
The next digit of our result is 9. 
Result so far: 109.0
The remainder is 35 after subtracting 351 from 386.
Bring next digit (6) of the dividend behind the 35 and repeat the process: 356 / 39

Going ahead to step 5:
356 divided by 39 is 9 with a remainder of 5.
Use 9 as the next digit of our solution. 
Result so far: 1099.0
If we subtract 351 from 356, we get 5.
Grab the next digit (6) from the dividend, add it to 5, then carry on: 56 / 39

On to step 6:
56 divided by 39 is 1 with a remainder of 17.
The next digit of our result is 1. 
Result so far: 10991.0
If we take 39 away from 56, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 7:
39 goes into 170 4 times with a remainder of 14.
Write down 4 as next digit of the result. 
Result so far: 10991.4
If we subtract 156 from 170, we get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Let's proceed to step 8:
The number 39 fits into 140 3 times, leaving a remainder of 23.
The number 3 becomes the next digit in our result. 
Result so far: 10991.43
Subtract 117 from 140 to get 23.
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 9:
39 can be fit into 230 5 times, resulting in a remainder of 35.
Use 5 as the next digit of our solution. 
Result so far: 10991.435
Subtracting 195 from 230 leaves us with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Let's proceed to step 10:
When dividing 350 by 39, we get 8 with a remainder of 38.
Record the quotient 8 as the next digit in the result. 
Result so far: 10991.4358
Subtract 312 from 350 to get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Let's proceed to step 11:
380 divided by 39 is 9 with a remainder of 29.
Record the quotient 9 as the next digit in the result. 
Result so far: 10991.43589
The remainder is 29 after subtracting 351 from 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Step 12:
The number 39 fits into 290 7 times, leaving a remainder of 17.
The number 7 becomes the next digit in our result. 
Result so far: 10991.435897
Deduct 273 from 290 and we're left with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Going ahead to step 13:
When dividing 170 by 39, we get 4 with a remainder of 14.
The number 4 becomes the next digit in our result. 
Result so far: 10991.4358974
If we take 156 away from 170, we end up with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Moving on to step 14:
When dividing 140 by 39, we get 3 with a remainder of 23.
The next digit of our result is 3. 
Result so far: 10991.43589743
The remainder is 23 after subtracting 117 from 140.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

In conclusion, the division gives 10991.43589743 with a balance of 2.3e-08.