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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 ## A sphere has a radius of x units. If the length of... tagged by: AAPL ##### This topic has 1 expert reply and 0 member replies ### Top Member ## A sphere has a radius of x units. If the length of... A sphere has a radius of x units. If the length of this radius is doubled, then how many times larger, in terms of volume, is the resultant sphere as compared with the original sphere? A) 1 B) 2 C) 4 D) 8 E) 16 The OA is D. Please, can any expert assist me with this PS question? I don't have it clear and I appreciate if any explain it for me. Thanks. ### GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Quote: A sphere has a radius of x units. If the length of this radius is doubled, then how many times larger, in terms of volume, is the resultant sphere as compared with the original sphere? A) 1 B) 2 C) 4 D) 8 E) 16 The OA is D. Please, can any expert assist me with this PS question? I don't have it clear and I appreciate if any explain it for me. Thanks. Hi AAPL, Let's take a look at your question. We know that a volume of a sphere with radius x can be represented as: $$V=\frac{4}{3}\pi x^3$$ If the length of this radius is doubled, the radius will become 2r and the volume V1 will be: $$V_1=\frac{4}{3}\pi\left(2x\right)^3$$ $$V_1=\frac{4}{3}\pi\left(8x^3\right)$$ $$V_1=8\times\frac{4}{3}\pi x^3$$ $$V_1=8V$$ It means that the resultant volume is 8 times larger than the original volume. Therefore, Option D is correct. Hope it helps. I am available if you'd like any follow up. _________________ 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 Study Smarter, Not Harder Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

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