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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 For any numbers a and b, a#b=a + b - ab. If a#b=0, which of This topic has 2 expert replies and 0 member replies Top Member For any numbers a and b, a#b=a + b - ab. If a#b=0, which of Timer 00:00 Your Answer A B C D E Global Stats Difficult For any numbers a and b, a#b=a + b - ab. If a#b=0, which of the following CANNOT be a value of b? A. 2 B. 1 C. 0 D. -1 E. -3/2 OA B Source: GMAT Prep GMAT/MBA Expert GMAT Instructor Joined 22 Aug 2016 Posted: 1975 messages Followed by: 30 members Upvotes: 470 BTGmoderatorDC wrote: For any numbers a and b, a#b = a + b - ab. If a#b = 0, which of the following CANNOT be a value of b? A. 2 B. 1 C. 0 D. -1 E. -3/2 OA B Source: GMAT Prep We have a#b = a + b - ab = 0 From a + b - ab = 0, we have a = 1/(b - 1) Since if b = 1, the value of a would be indeterminable, we have b ≠ 1. The correct answer: B Hope this helps! -Jay _________________ Manhattan Review GMAT Prep Locations: GRE Manhattan | TOEFL Prep Courses Boston | IELTS Prep Courses San Francisco | Philadelphia ACT Tutoring | and many more... Schedule your free consultation with an experienced GMAT Prep Advisor! Click here. GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2791 messages Followed by: 18 members Upvotes: 43 BTGmoderatorDC wrote: For any numbers a and b, a#b=a + b - ab. If a#b=0, which of the following CANNOT be a value of b? A. 2 B. 1 C. 0 D. -1 E. -3/2 OA B Source: GMAT Prep We are given that a#b=a + b - ab and that a#b=0. Thus we have a + b - ab = 0 a + b = ab Now let’s look at the choices: A. If b = 2, then a + 2 = a(2) 2 = a So b can be 2. B. If b = 1, then a + 1 = a(1) We see that a + 1 (1 more than a) can’t be equal to a itself. So b CANNOT be 1, and that is the number we are looking for. Alternate Solution: We are given that a#b=a + b - ab and that a#b=0. Thus we have a + b - ab = 0 a + b = ab b = ab - a b = a(b - 1) We observe here that b = 1 results in the inconsistent result of 1 = 0. Thus, the only value that b cannot assume is 1. Answer: B • Magoosh Study with Magoosh GMAT prep 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 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 • FREE GMAT Exam Know how you'd score today for$0

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