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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote If 9^y + 3^b=10*3^b, then 2y=? tagged by: BTGmoderatorLU This topic has 2 expert replies and 0 member replies Top Member If 9^y + 3^b=10*3^b, then 2y=? $$If\ \ 9^y+3^b=10*3^b,\ \ then\ \ 2y=?$$ (A) b-2 (B) b-1 (C) b (D) b+1 (E) b+2 The OA is E. I'm confused with this PS question. Please, can any expert assist me with it? Thanks in advanced. GMAT/MBA Expert Elite Legendary Member Joined 23 Jun 2013 Posted: 10197 messages Followed by: 497 members Upvotes: 2867 GMAT Score: 800 Hi LUANDATO, While this question might look 'scary', it can be solved rather easily by TESTing VALUES. Since B appears on both sides of the equation, we'll TEST a value for B and then solve for Y.... IF... B = 0 (9^Y) + (3^0) = (10)(3^0) (9^Y) + 1 = (10)(1) (9^Y) = 9 Y = 1 The question asks for the value of 2Y, so we're looking for an answer that equals 2 when B=0. There's only one answer that matches... Final Answer: E GMAT assassins aren't born, they're made, Rich _________________ Contact Rich at Rich.C@empowergmat.com GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Quote: $$If\ \ 9^y+3^b=10*3^b,\ \ then\ \ 2y=?$$ (A) b-2 (B) b-1 (C) b (D) b+1 (E) b+2 The OA is E. I'm confused with this PS question. Please, can any expert assist me with it? Thanks in advanced. Hi LUANDATO, Lets take a look at your question. $$9^y+3^b=10\times3^b$$ $$\left(3^2\right)^y+3^b=10\times3^b$$ $$\left(3^2\right)^y=10\times3^b-3^b$$ $$3^{2y}=10\times3^b-3^b$$ $$3^{2y}=3^b\left(10-1\right)$$ $$3^{2y}=3^b\left(9\right)$$ $$3^{2y}=3^b\left(3^2\right)$$ $$3^{2y}=3^{b+2}$$ Since bases are equivalent, therefore, exponents will be equal as well, $$2y=b+2$$ Therefore, Option E is correct. Hope it helps. I am available if you'd like any followup. _________________ GMAT Prep From The Economist We offer 70+ point score improvement money back guarantee. Our average student improves 98 points. Free 7-Day Test Prep with Economist GMAT Tutor - Receive free access to the top-rated GMAT prep course including a 1-on-1 strategy session, 2 full-length tests, and 5 ask-a-tutor messages. Get started now. • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • 1 Hour Free BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

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