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
Difficult DS
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(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
(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