We're dividing 438438 by 25 
The aim is to understand the frequency of 25 in 438438.

Moving on to step 1:
4 divided by 25 is 0 with a remainder of 4.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 4, we get 4.
Bring next digit (3) of the dividend behind the 4 and repeat the process: 43 / 25

On to step 2:
When dividing 43 by 25, we get 1 with a remainder of 18.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 25 from 43 and we're left with 18.
Include the next digit (8) from the dividend after 18, then repeat: 188 / 25

Going ahead to step 3:
The number 25 fits into 188 7 times, leaving a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 17.0
If we take 175 away from 188, we end up with 13.
Take the next digit (4) from the dividend and append it to 13, then repeat: 134 / 25

Let's proceed to step 4:
When dividing 134 by 25, we get 5 with a remainder of 9.
Put 5 as the next digit of the answer. 
Result so far: 175.0
If we subtract 125 from 134, we get 9.
Append the next digit (3) from the dividend to 9 and continue with: 93 / 25

Moving on to step 5:
If we divide 93 by 25, we get 3 and a remainder of 18.
The number 3 becomes the next digit in our result. 
Result so far: 1753.0
Subtracting 75 from 93 leaves us with 18.
Bring next digit (8) of the dividend behind the 18 and repeat the process: 188 / 25

Going ahead to step 6:
25 goes into 188 7 times with a remainder of 13.
Use 7 as the next digit of our solution. 
Result so far: 17537.0
Deduct 175 from 188 and we're left with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 7:
If we divide 130 by 25, we get 5 and a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 17537.5
If we take 125 away from 130, we end up with 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 8:
When dividing 50 by 25, we get 2 with a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 17537.52
The remainder is 0 after subtracting 50 from 50.
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:
25 can be fit into 0 0 times, resulting in a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 17537.52
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 10:
If we divide 0 by 25, we get 0 and a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 17537.52
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.

Our division results in 17537.52 with a remaining 0.0.