315866 divided by 39 
The aim is to understand the frequency of 39 in 315866.

Advancing to step 1:
39 goes into 3 0 times with a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 3, we get 3.
Fetch the next digit (1) from the dividend, attach it to 3 and continue: 31 / 39

Going ahead to step 2:
39 can be fit into 31 0 times, resulting in a remainder of 31.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 31, we end up with 31.
Grab the next digit (5) from the dividend, add it to 31, then carry on: 315 / 39

On to step 3:
39 can be fit into 315 8 times, resulting in a remainder of 3.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
Subtracting 312 from 315 leaves us with 3.
Grab the next digit (8) from the dividend, add it to 3, then carry on: 38 / 39

On to step 4:
39 can be fit into 38 0 times, resulting in a remainder of 38.
Record the quotient 0 as the next digit in the result. 
Result so far: 80.0
Deduct 0 from 38 and we're left with 38.
Take the next digit (6) from the dividend and append it to 38, then repeat: 386 / 39

Going ahead to step 5:
When dividing 386 by 39, we get 9 with a remainder of 35.
The next digit of our result is 9. 
Result so far: 809.0
If we subtract 351 from 386, we get 35.
Grab the next digit (6) from the dividend, add it to 35, then carry on: 356 / 39

Going ahead to step 6:
356 divided by 39 is 9 with a remainder of 5.
The next digit of our result is 9. 
Result so far: 8099.0
If we subtract 351 from 356, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 7:
The number 39 fits into 50 1 times, leaving a remainder of 11.
Use 1 as the next digit of our solution. 
Result so far: 8099.1
If we subtract 39 from 50, we get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 8:
39 can be fit into 110 2 times, resulting in a remainder of 32.
Record the quotient 2 as the next digit in the result. 
Result so far: 8099.12
Deduct 78 from 110 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.

Let's proceed to step 9:
The number 39 fits into 320 8 times, leaving a remainder of 8.
The next digit of our result is 8. 
Result so far: 8099.128
The remainder is 8 after subtracting 312 from 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 10:
When dividing 80 by 39, we get 2 with a remainder of 2.
The number 2 becomes the next digit in our result. 
Result so far: 8099.1282
If we take 78 away from 80, we end up with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 11:
39 can be fit into 20 0 times, resulting in a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 8099.1282
If we take 0 away from 20, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 12:
200 divided by 39 is 5 with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 8099.128205
Subtract 195 from 200 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 13:
39 goes into 50 1 times with a remainder of 11.
Use 1 as the next digit of our solution. 
Result so far: 8099.1282051
If we take 39 away from 50, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Advancing to step 14:
When dividing 110 by 39, we get 2 with a remainder of 32.
The next digit of our result is 2. 
Result so far: 8099.12820512
Subtract 78 from 110 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

The final outcome is 8099.12820512, with a leftover of 3.2e-08.