Check whether 25n can end with the digit zero for any natural number.
@Vidhya Harihara. : Nice work . Keep it up .
25n = (5 X 5)n
If we raise 5 to any power ,unit digit will only be 5 .
For any natural number to end with 0 , it must be a factor of 10 so it must have factors both 2 and 5 .But 25 does not have 2 as a factor.
Thus 25n cannot end with 0 for any natural number n
​Hope this would have cleared your doubt .