Unit digit

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Unit digit

by Captchar » Sun Dec 16, 2012 4:49 am
The unit digit of 2^34 x 3^45 x 4^56 x 5^67 x 6^78 x 7^89 is
A) 0
B) 1
C) 2
D) 3
E) 4

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by Anurag@Gurome » Sun Dec 16, 2012 4:51 am
Captchar wrote:The unit digit of 2^34 x 3^45 x 4^56 x 5^67 x 6^78 x 7^89 is
The given product is multiple of 2 and 5, i.e multiple of 10.
Hence, the unit's digit of the product is 0.

The correct answer is A.
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by Jim@StratusPrep » Mon Dec 17, 2012 4:42 pm
Always look for a short step with these long problems... 5 x 2 = 10 so the ones digit will always be 0.
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