We're dividing 25595705 by 644 
The aim is to understand the frequency of 644 in 25595705.

Step 1:
2 divided by 644 is 0 with a remainder of 2.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Take the next digit (5) from the dividend and append it to 2, then repeat: 25 / 644

Step 2:
644 goes into 25 0 times with a remainder of 25.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 25, we end up with 25.
Bring next digit (5) of the dividend behind the 25 and repeat the process: 255 / 644

Going ahead to step 3:
The number 644 fits into 255 0 times, leaving a remainder of 255.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 255 leaves us with 255.
Append the next digit (9) from the dividend to 255 and continue with: 2559 / 644

Going ahead to step 4:
The number 644 fits into 2559 3 times, leaving a remainder of 627.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
If we subtract 1932 from 2559, we get 627.
Append the next digit (5) from the dividend to 627 and continue with: 6275 / 644

Moving on to step 5:
If we divide 6275 by 644, we get 9 and a remainder of 479.
Use 9 as the next digit of our solution. 
Result so far: 39.0
The remainder is 479 after subtracting 5796 from 6275.
Bring next digit (7) of the dividend behind the 479 and repeat the process: 4797 / 644

Advancing to step 6:
The number 644 fits into 4797 7 times, leaving a remainder of 289.
The next digit of our result is 7. 
Result so far: 397.0
Subtracting 4508 from 4797 leaves us with 289.
Fetch the next digit (0) from the dividend, attach it to 289 and continue: 2890 / 644

Moving on to step 7:
2890 divided by 644 is 4 with a remainder of 314.
Write down 4 as next digit of the result. 
Result so far: 3974.0
Deduct 2576 from 2890 and we're left with 314.
Include the next digit (5) from the dividend after 314, then repeat: 3145 / 644

On to step 8:
If we divide 3145 by 644, we get 4 and a remainder of 569.
The next digit of our result is 4. 
Result so far: 39744.0
Deduct 2576 from 3145 and we're left with 569.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5690, and continue the process.

On to step 9:
When dividing 5690 by 644, we get 8 with a remainder of 538.
Record the quotient 8 as the next digit in the result. 
Result so far: 39744.8
If we take 5152 away from 5690, we end up with 538.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5380, and continue the process.

Advancing to step 10:
5380 divided by 644 is 8 with a remainder of 228.
Record the quotient 8 as the next digit in the result. 
Result so far: 39744.88
Deduct 5152 from 5380 and we're left with 228.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2280, and continue the process.

After the division, we end up with 39744.88 and a remainder of 0.228.