We divide 664401 by 25
The aim is to understand the frequency of 25 in 664401.

Step 1:
6 divided by 25 is 0 with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Grab the next digit (6) from the dividend, add it to 6, then carry on: 66 / 25

Moving on to step 2:
When dividing 66 by 25, we get 2 with a remainder of 16.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
If we take 50 away from 66, we end up with 16.
Bring next digit (4) of the dividend behind the 16 and repeat the process: 164 / 25

Moving on to step 3:
25 can be fit into 164 6 times, resulting in a remainder of 14.
Record the quotient 6 as the next digit in the result. 
Result so far: 26.0
The remainder is 14 after subtracting 150 from 164.
Fetch the next digit (4) from the dividend, attach it to 14 and continue: 144 / 25

Moving on to step 4:
144 divided by 25 is 5 with a remainder of 19.
Put 5 as the next digit of the answer. 
Result so far: 265.0
Deduct 125 from 144 and we're left with 19.
Bring next digit (0) of the dividend behind the 19 and repeat the process: 190 / 25

Advancing to step 5:
If we divide 190 by 25, we get 7 and a remainder of 15.
Put 7 as the next digit of the answer. 
Result so far: 2657.0
Deduct 175 from 190 and we're left with 15.
Include the next digit (1) from the dividend after 15, then repeat: 151 / 25

Moving on to step 6:
25 goes into 151 6 times with a remainder of 1.
Record the quotient 6 as the next digit in the result. 
Result so far: 26576.0
If we subtract 150 from 151, we get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Step 7:
10 divided by 25 is 0 with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 26576.0
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Step 8:
If we divide 100 by 25, we get 4 and a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 26576.04
Deduct 100 from 100 and we're left 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 9:
0 divided by 25 is 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 26576.04
Subtracting 0 from 0 leaves us 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.

Let's proceed to step 10:
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: 26576.04
Subtracting 0 from 0 leaves us 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.

The quotient of the division is 26576.04, and the remainder is 0.0.