Let's divide 511823 by 39
The aim is to understand the frequency of 39 in 511823.

On to step 1:
39 goes into 5 0 times with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Fetch the next digit (1) from the dividend, attach it to 5 and continue: 51 / 39

On to step 2:
When dividing 51 by 39, we get 1 with a remainder of 12.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 12 after subtracting 39 from 51.
Include the next digit (1) from the dividend after 12, then repeat: 121 / 39

Moving on to step 3:
The number 39 fits into 121 3 times, leaving a remainder of 4.
Record the quotient 3 as the next digit in the result. 
Result so far: 13.0
Deduct 117 from 121 and we're left with 4.
Fetch the next digit (8) from the dividend, attach it to 4 and continue: 48 / 39

Let's proceed to step 4:
If we divide 48 by 39, we get 1 and a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 131.0
If we subtract 39 from 48, we get 9.
Grab the next digit (2) from the dividend, add it to 9, then carry on: 92 / 39

Let's proceed to step 5:
92 divided by 39 is 2 with a remainder of 14.
The number 2 becomes the next digit in our result. 
Result so far: 1312.0
Subtract 78 from 92 to get 14.
Bring next digit (3) of the dividend behind the 14 and repeat the process: 143 / 39

Moving on to step 6:
When dividing 143 by 39, we get 3 with a remainder of 26.
Put 3 as the next digit of the answer. 
Result so far: 13123.0
If we subtract 117 from 143, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Let's proceed to step 7:
The number 39 fits into 260 6 times, leaving a remainder of 26.
The next digit of our result is 6. 
Result so far: 13123.6
Subtract 234 from 260 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Moving on to step 8:
39 goes into 260 6 times with a remainder of 26.
Record the quotient 6 as the next digit in the result. 
Result so far: 13123.66
If we take 234 away from 260, we end up with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

After the division, we end up with 13123.66 and a remainder of 0.026.