We divide 621709 by 15
The aim is to understand the frequency of 15 in 621709.

Going ahead to step 1:
The number 15 fits into 6 0 times, leaving a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Take the next digit (2) from the dividend and append it to 6, then repeat: 62 / 15

Moving on to step 2:
15 can be fit into 62 4 times, resulting in a remainder of 2.
Use 4 as the next digit of our solution. 
Result so far: 4.0
The remainder is 2 after subtracting 60 from 62.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 15

Step 3:
15 goes into 21 1 times with a remainder of 6.
Use 1 as the next digit of our solution. 
Result so far: 41.0
If we subtract 15 from 21, we get 6.
Append the next digit (7) from the dividend to 6 and continue with: 67 / 15

Going ahead to step 4:
15 can be fit into 67 4 times, resulting in a remainder of 7.
Write down 4 as next digit of the result. 
Result so far: 414.0
Subtract 60 from 67 to get 7.
Grab the next digit (0) from the dividend, add it to 7, then carry on: 70 / 15

Step 5:
When dividing 70 by 15, we get 4 with a remainder of 10.
The number 4 becomes the next digit in our result. 
Result so far: 4144.0
The remainder is 10 after subtracting 60 from 70.
Include the next digit (9) from the dividend after 10, then repeat: 109 / 15

Going ahead to step 6:
15 goes into 109 7 times with a remainder of 4.
The next digit of our result is 7. 
Result so far: 41447.0
Subtracting 105 from 109 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 7:
The number 15 fits into 40 2 times, leaving a remainder of 10.
Put 2 as the next digit of the answer. 
Result so far: 41447.2
Deduct 30 from 40 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 8:
If we divide 100 by 15, we get 6 and a remainder of 10.
Put 6 as the next digit of the answer. 
Result so far: 41447.26
If we take 90 away from 100, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 9:
15 can be fit into 100 6 times, resulting in a remainder of 10.
The number 6 becomes the next digit in our result. 
Result so far: 41447.266
Subtracting 90 from 100 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final result is 41447.266 with a remainder of 0.001.