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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 the circumference of circle P is 15.174 and the circumfer ##### This topic has 2 expert replies and 0 member replies ## If the circumference of circle P is 15.174 and the circumfer If the circumference of circle P is 15.174 and the circumference of circle Q is 6.28, then the diameter of circle P minus the diameter of circle Q is approximately equal to (A) 1.5 (B) 3.0 (C) 5.5 (D) 9.0 (E) 9.4 Is there a strategic approach to this question? Please I need any experts help. ### GMAT/MBA Expert GMAT Instructor Joined 25 May 2010 Posted: 15386 messages Followed by: 1872 members Upvotes: 13060 GMAT Score: 790 ardz24 wrote: If the circumference of circle P is 15.174 and the circumference of circle Q is 6.28, then the diameter of circle P minus the diameter of circle Q is approximately equal to (A) 1.5 (B) 3.0 (C) 5.5 (D) 9.0 (E) 9.4 Is there a strategic approach to this question? Please I need any experts help. C = Ï€d â‰ˆ 3d. Circle P: 3d â‰ˆ 15.174 3d â‰ˆ 15 d â‰ˆ 5. Circle Q: 3d â‰ˆ 6.28 3d â‰ˆ 6 d â‰ˆ 2. Thus: Approximate difference between the diameters = 5-2 = 3. The correct answer is B. _________________ Mitch Hunt Private Tutor for the GMAT and GRE GMATGuruNY@gmail.com If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon. Available for tutoring in NYC and long-distance. For more information, please email me at GMATGuruNY@gmail.com. Student Review #1 Student Review #2 Student Review #3 Free GMAT Practice Test How can you improve your test score if you don't know your baseline score? Take a free online practice exam. Get started on achieving your dream score today! Sign up now. ### GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Quote: If the circumference of circle P is 15.174 and the circumference of circle Q is 6.28, then the diameter of circle P minus the diameter of circle Q is approximately equal to (A) 1.5 (B) 3.0 (C) 5.5 (D) 9.0 (E) 9.4 Is there a strategic approach to this question? Please I need any experts help. Hi ardz24, Let's take a look at your question. Let's find the diameter of circle P using circumference formula: $$Circumference=2\pi r$$ $$15.174=2\pi r$$ $$2r=\frac{15.174}{\pi}$$ $$\pi=3.14\approx3$$ $$2r=\frac{15.174}{3}$$ $$2r\approx5$$ $$Diameter\approx5$$ Diameter of Circle P is 5. Let's now find the diameter of circle Q using circumference formula: $$Circumference=2\pi r$$ $$6.28=2\pi r$$ $$2r=\frac{6.28}{\pi}$$ $$2r=\frac{6.28}{3}$$ $$2r\approx2$$ $$Diameter\approx2$$ Diameter of Circle Q is 2. Diameter of Circle P - Diameter of Circle Q $$=5-2$$ $$=3$$ Therefore, Option B 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. • FREE GMAT Exam Know how you'd score today for$0

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