Q5 of 18 Page 11

Check whether 6n can end with the digit 0 for any natural number n.

If any number has last digit 0,


Then, it should be divisible by 10


Factors of 10 = 2×5


So,


Value 6n should be divisible by 2 or 5


Prime factorisation of 6n = (2×3)n


Hence,


6n is divisible by 2 but not by 5.


It can not end with 0.


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