Difficult DS

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Difficult DS

by roy_priya » Sat Jun 28, 2008 7:48 am
What do you think is the answer? I will post the OA later

Is 5^k less than 1,000 ?
(1) 5^(k-1) > 3000
(2) 5^(k-1) = 5^k - 500

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by TRANGZON » Sat Jun 28, 2008 8:48 am
I think the question can be understood:

Is k<4>6
(2) k=4

So, OA is D. What is OA?

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by arvindm07 » Sat Jun 28, 2008 8:51 am
I got the answer to be D.

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by atlantic » Sat Jun 28, 2008 11:37 am
(1) 5^(k-1)>3,000 <5>3,000 <5>15,000 so is enough to answer the question, SUFF

(2) 5^(K-1)=(5^k)-500 <-> (5^k)*(1/5)=(5^k)-500 <-> 5^k=5^(k+1)-2,500 <-> 5^k-5^(k+1)=-2,500 <-> 5^k(1-5)=-2,500 <-> 5^k=625, enough to answer the question, SUFF

Ans is D