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How many cups of water do you need to serve your friends?

+1 vote
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You have a large number of friends coming over and they all get thirsty. Your first friend asks for 1/2 a cup of water. Your second friend asks for 1/4 a cup of water. Your third friend asks for 1/8 a cup of water, etc.

How many cups of water do you need to serve your friends?

posted May 13, 2015 by Anamika

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1 Answer

+2 votes

Sum of infinite GP , a/(1-r) , here a=r=1/2 ;;; a=first term ;;; r=common ratio

so answer is (1/2)/(1-(1/2)) == 1

answer May 13, 2015 by Ankit Kamboj



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