We're dividing 638502 by 30 
The aim is to understand the frequency of 30 in 638502.

On to step 1:
The number 30 fits into 6 0 times, leaving a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Take the next digit (3) from the dividend and append it to 6, then repeat: 63 / 30

On to step 2:
30 can be fit into 63 2 times, resulting in a remainder of 3.
Write down 2 as next digit of the result. 
Result so far: 2.0
If we take 60 away from 63, we end up with 3.
Fetch the next digit (8) from the dividend, attach it to 3 and continue: 38 / 30

Going ahead to step 3:
30 goes into 38 1 times with a remainder of 8.
The next digit of our result is 1. 
Result so far: 21.0
The remainder is 8 after subtracting 30 from 38.
Include the next digit (5) from the dividend after 8, then repeat: 85 / 30

Moving on to step 4:
85 divided by 30 is 2 with a remainder of 25.
Write down 2 as next digit of the result. 
Result so far: 212.0
Deduct 60 from 85 and we're left with 25.
Fetch the next digit (0) from the dividend, attach it to 25 and continue: 250 / 30

On to step 5:
250 divided by 30 is 8 with a remainder of 10.
Put 8 as the next digit of the answer. 
Result so far: 2128.0
If we take 240 away from 250, we end up with 10.
Append the next digit (2) from the dividend to 10 and continue with: 102 / 30

Moving on to step 6:
102 divided by 30 is 3 with a remainder of 12.
Put 3 as the next digit of the answer. 
Result so far: 21283.0
Subtracting 90 from 102 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Let's proceed to step 7:
30 can be fit into 120 4 times, resulting in a remainder of 0.
Record the quotient 4 as the next digit in the result. 
Result so far: 21283.4
If we take 120 away from 120, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
30 goes into 0 0 times with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 21283.4
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 9:
0 divided by 30 is 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 21283.4
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

After the division, we end up with 21283.4 and a remainder of 0.0.