We're dividing 15307390 by 815 
The aim is to understand the frequency of 815 in 15307390.

On to step 1:
If we divide 1 by 815, we get 0 and a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Include the next digit (5) from the dividend after 1, then repeat: 15 / 815

Let's proceed to step 2:
15 divided by 815 is 0 with a remainder of 15.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 15 and we're left with 15.
Bring next digit (3) of the dividend behind the 15 and repeat the process: 153 / 815

Let's proceed to step 3:
815 goes into 153 0 times with a remainder of 153.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 153 after subtracting 0 from 153.
Fetch the next digit (0) from the dividend, attach it to 153 and continue: 1530 / 815

Moving on to step 4:
815 goes into 1530 1 times with a remainder of 715.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtracting 815 from 1530 leaves us with 715.
Grab the next digit (7) from the dividend, add it to 715, then carry on: 7157 / 815

Let's proceed to step 5:
815 goes into 7157 8 times with a remainder of 637.
Record the quotient 8 as the next digit in the result. 
Result so far: 18.0
Deduct 6520 from 7157 and we're left with 637.
Grab the next digit (3) from the dividend, add it to 637, then carry on: 6373 / 815

Moving on to step 6:
815 can be fit into 6373 7 times, resulting in a remainder of 668.
Record the quotient 7 as the next digit in the result. 
Result so far: 187.0
Deduct 5705 from 6373 and we're left with 668.
Grab the next digit (9) from the dividend, add it to 668, then carry on: 6689 / 815

Step 7:
When dividing 6689 by 815, we get 8 with a remainder of 169.
The number 8 becomes the next digit in our result. 
Result so far: 1878.0
Deduct 6520 from 6689 and we're left with 169.
Grab the next digit (0) from the dividend, add it to 169, then carry on: 1690 / 815

Let's proceed to step 8:
When dividing 1690 by 815, we get 2 with a remainder of 60.
Put 2 as the next digit of the answer. 
Result so far: 18782.0
The remainder is 60 after subtracting 1630 from 1690.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Moving on to step 9:
When dividing 600 by 815, we get 0 with a remainder of 600.
Record the quotient 0 as the next digit in the result. 
Result so far: 18782.0
The remainder is 600 after subtracting 0 from 600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6000, and continue the process.

On to step 10:
6000 divided by 815 is 7 with a remainder of 295.
Use 7 as the next digit of our solution. 
Result so far: 18782.07
Subtracting 5705 from 6000 leaves us with 295.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2950, and continue the process.

Going ahead to step 11:
815 can be fit into 2950 3 times, resulting in a remainder of 505.
Use 3 as the next digit of our solution. 
Result so far: 18782.073
Deduct 2445 from 2950 and we're left with 505.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5050, and continue the process.

Going ahead to step 12:
When dividing 5050 by 815, we get 6 with a remainder of 160.
Record the quotient 6 as the next digit in the result. 
Result so far: 18782.0736
Subtracting 4890 from 5050 leaves us with 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

On to step 13:
815 can be fit into 1600 1 times, resulting in a remainder of 785.
Use 1 as the next digit of our solution. 
Result so far: 18782.07361
If we subtract 815 from 1600, we get 785.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7850, and continue the process.

Moving on to step 14:
When dividing 7850 by 815, we get 9 with a remainder of 515.
The number 9 becomes the next digit in our result. 
Result so far: 18782.073619
Subtract 7335 from 7850 to get 515.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5150, and continue the process.

Advancing to step 15:
815 can be fit into 5150 6 times, resulting in a remainder of 260.
The next digit of our result is 6. 
Result so far: 18782.0736196
Subtract 4890 from 5150 to get 260.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2600, and continue the process.

Step 16:
When dividing 2600 by 815, we get 3 with a remainder of 155.
The next digit of our result is 3. 
Result so far: 18782.07361963
Subtract 2445 from 2600 to get 155.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1550, and continue the process.

The quotient of the division is 18782.07361963, and the remainder is 1.55e-07.