510197 ÷ 39 
The aim is to understand the frequency of 39 in 510197.

Step 1:
If we divide 5 by 39, we get 0 and a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 5 leaves us with 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 39

Moving on to step 2:
When dividing 51 by 39, we get 1 with a remainder of 12.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we subtract 39 from 51, we get 12.
Append the next digit (0) from the dividend to 12 and continue with: 120 / 39

On to step 3:
39 goes into 120 3 times with a remainder of 3.
Record the quotient 3 as the next digit in the result. 
Result so far: 13.0
Subtracting 117 from 120 leaves us with 3.
Fetch the next digit (1) from the dividend, attach it to 3 and continue: 31 / 39

On to step 4:
The number 39 fits into 31 0 times, leaving a remainder of 31.
Use 0 as the next digit of our solution. 
Result so far: 130.0
Deduct 0 from 31 and we're left with 31.
Fetch the next digit (9) from the dividend, attach it to 31 and continue: 319 / 39

Step 5:
When dividing 319 by 39, we get 8 with a remainder of 7.
Use 8 as the next digit of our solution. 
Result so far: 1308.0
If we take 312 away from 319, we end up with 7.
Include the next digit (7) from the dividend after 7, then repeat: 77 / 39

Step 6:
39 can be fit into 77 1 times, resulting in a remainder of 38.
Record the quotient 1 as the next digit in the result. 
Result so far: 13081.0
Deduct 39 from 77 and we're left with 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Step 7:
39 can be fit into 380 9 times, resulting in a remainder of 29.
The number 9 becomes the next digit in our result. 
Result so far: 13081.9
Deduct 351 from 380 and we're left with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Step 8:
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: 13081.97
Subtracting 273 from 290 leaves us 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 9:
If we divide 170 by 39, we get 4 and a remainder of 14.
The next digit of our result is 4. 
Result so far: 13081.974
Subtracting 156 from 170 leaves us 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.

Going ahead to step 10:
If we divide 140 by 39, we get 3 and a remainder of 23.
The number 3 becomes the next digit in our result. 
Result so far: 13081.9743
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.

Let's proceed to step 11:
39 can be fit into 230 5 times, resulting in a remainder of 35.
Write down 5 as next digit of the result. 
Result so far: 13081.97435
Subtract 195 from 230 to get 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 12:
When dividing 350 by 39, we get 8 with a remainder of 38.
Use 8 as the next digit of our solution. 
Result so far: 13081.974358
Subtracting 312 from 350 leaves us with 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Advancing to step 13:
39 goes into 380 9 times with a remainder of 29.
Put 9 as the next digit of the answer. 
Result so far: 13081.9743589
Subtract 351 from 380 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Advancing to step 14:
290 divided by 39 is 7 with a remainder of 17.
Use 7 as the next digit of our solution. 
Result so far: 13081.97435897
If we subtract 273 from 290, we get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

The final result is 13081.97435897 with a remainder of 1.7e-08.