The
right most non zero digit of the number 302720 is

(A)1
(B) 3 (C) 7 (D) 9
Solution follows here:

__Solution:__
30

^{2720}= 3^{2720}* 10^{2720}
As 10

^{2720}produces all zeroes from right side, the last digit (unit digit) of 3^{2720}
is the right most non zero digit of 30

^{2720}.
To find the unit digit of 3

^{2720}:**(Please refer to “Magic of Numbers-1(unit digit...)” post of this blog)**

As 2720 is multiple of 4, we consider 4

^{th}digit of the unit digit pattern of 3^{n}.
The unit digit pattern of 3

Answer is ^{n}is 3,9,7,**1****(A)**

Thanks for Good expiation.

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