21016 divided by 25 
The aim is to understand the frequency of 25 in 21016.

Going ahead to step 1:
If we divide 2 by 25, we get 0 and a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 25

Moving on to step 2:
25 can be fit into 21 0 times, resulting in a remainder of 21.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 21 and we're left with 21.
Fetch the next digit (0) from the dividend, attach it to 21 and continue: 210 / 25

Step 3:
25 goes into 210 8 times with a remainder of 10.
Use 8 as the next digit of our solution. 
Result so far: 8.0
Deduct 200 from 210 and we're left with 10.
Take the next digit (1) from the dividend and append it to 10, then repeat: 101 / 25

Going ahead to step 4:
When dividing 101 by 25, we get 4 with a remainder of 1.
The number 4 becomes the next digit in our result. 
Result so far: 84.0
Subtracting 100 from 101 leaves us with 1.
Fetch the next digit (6) from the dividend, attach it to 1 and continue: 16 / 25

Step 5:
The number 25 fits into 16 0 times, leaving a remainder of 16.
Record the quotient 0 as the next digit in the result. 
Result so far: 840.0
If we take 0 away from 16, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Moving on to step 6:
25 can be fit into 160 6 times, resulting in a remainder of 10.
Write down 6 as next digit of the result. 
Result so far: 840.6
If we take 150 away from 160, 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.

Step 7:
25 can be fit into 100 4 times, resulting in a remainder of 0.
Write down 4 as next digit of the result. 
Result so far: 840.64
Subtracting 100 from 100 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.

Advancing to step 8:
If we divide 0 by 25, we get 0 and a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 840.64
If we subtract 0 from 0, we 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.

On to step 9:
If we divide 0 by 25, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 840.64
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 840.64 and a remainder of 0.0.