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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 x + x^2 + x^3 = 27, then the average (arithmetic mean) tagged by: M7MBA This topic has 1 expert reply and 1 member reply If x + x^2 + x^3 = 27, then the average (arithmetic mean) Timer 00:00 Your Answer A B C D E Global Stats Difficult If x + x^2 + x^3 = 27, then the average (arithmetic mean) of x + x^2 + x^3 + x^4 is equal to which of the following? A. 3 B. 3x C. 7x D. 9 E. 9x OA=C Source: Veritas Prep Legendary Member Joined 10 May 2014 Posted: 1079 messages Followed by: 23 members Upvotes: 205 M7MBA wrote: If x + x^2 + x^3 = 27, then the average (arithmetic mean) of x + x^2 + x^3 + x^4 is equal to which of the following? A. 3 B. 3x C. 7x D. 9 E. 9x OA=C Source: Veritas Prep Average = (x + x^2 + x^3 + x^4)/4 = x (1 + x+ x^2 + x^3 )/4 = x(1+27)/4 = 28x/4 = 7x Answer: Option C _________________ Bhoopendra Singh & Sushma Jha - Founder "GMATinsight" Testimonials e-mail: info@GMATinsight.com I Mobile: +91-9999687183 / +91-9891333772 To register for One-on-One FREE ONLINE DEMO Class Call/e-mail One-On-One Private tutoring fee - US$40 per hour & for FULL COURSE (38 LIVE Sessions)-US$1000 GMAT/MBA Expert GMAT Instructor Joined 25 May 2010 Posted: 15344 messages Followed by: 1864 members Upvotes: 13060 GMAT Score: 790 [quote="GMATinsight"] M7MBA wrote: If x + x^2 + x^3 = 27, then the average (arithmetic mean) of x + x^2 + x^3 + x^4 is equal to which of the following? A. 3 B. 3x C. 7x D. 9 E. 9x We can PLUG IN THE ANSWERS, which represent the average of x + x² + x³ + x⁴. Test B: (x + x² + x³ + x⁴)/4 = 3x Multiplying both sides by 4, we get: x + x² + x³ + x⁴ = 12x Dividing both sides by x, we get: 1 + x + x² + x³ = 12 Substituting x+x²+x³=27 into 1+x+x²+x³ = 12, we get: 1 + 27 = 12 28 = 12 The right side needs to be greater. Test C: (x + x² + x³ + x⁴)/4 = 7x Multiplying both sides by 4, we get: x + x² + x³ + x⁴ = 28x Dividing both sides by x, we get: 1 + x + x² + x³ = 28 Substituting x+x²+x³=27 into 1+x+x²+x³ = 28, we get: 1 + 27 = 28 28 = 28 Success! The correct answer is C. _________________ 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. • Free Trial & Practice Exam BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • 1 Hour Free BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • 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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