21861 ÷ 25 
We're looking to find how many times 25 goes into 21861.

Advancing to step 1:
25 goes into 2 0 times with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 25

Step 2:
The number 25 fits into 21 0 times, leaving a remainder of 21.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 21 to get 21.
Include the next digit (8) from the dividend after 21, then repeat: 218 / 25

On to step 3:
25 can be fit into 218 8 times, resulting in a remainder of 18.
The next digit of our result is 8. 
Result so far: 8.0
Subtracting 200 from 218 leaves us with 18.
Grab the next digit (6) from the dividend, add it to 18, then carry on: 186 / 25

Let's proceed to step 4:
25 goes into 186 7 times with a remainder of 11.
Use 7 as the next digit of our solution. 
Result so far: 87.0
If we take 175 away from 186, we end up with 11.
Append the next digit (1) from the dividend to 11 and continue with: 111 / 25

Moving on to step 5:
25 can be fit into 111 4 times, resulting in a remainder of 11.
Record the quotient 4 as the next digit in the result. 
Result so far: 874.0
Subtracting 100 from 111 leaves us with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 6:
110 divided by 25 is 4 with a remainder of 10.
Use 4 as the next digit of our solution. 
Result so far: 874.4
If we take 100 away from 110, 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:
The number 25 fits into 100 4 times, leaving a remainder of 0.
The next digit of our result is 4. 
Result so far: 874.44
The remainder is 0 after subtracting 100 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 874.44, with a leftover of 0.0.