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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 positive integer values of n, the operation . . . . . tagged by: Vincen This topic has 1 expert reply and 0 member replies For positive integer values of n, the operation . . . . . For positive integer values of n, the operation n# is defined as the sum of all integers from 1 to n, inclusive. For example, 4# = 1 + 2 + 3 + 4 = 10. If 15# - 14# = k#, what is the value of k#? A. 1 B. 4 C. 5 D. 14 E. 15 The OA is the option E. Is there an easy way to solve this PS question without making the whole calculation? I need your help experts. Thanks in advanced. GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Top Reply Hello Vincen. Let's take a look at your question. We have to solve 15#-14#=k#. But, we have to notice that 15# = 15 + 14#. Now, we can rewrite 15#-14#=k# as follows: $$k\# = 15\#-14\#\ =\ 15\ +\ 14\#\ -\ 14\#\ =\ 15 .$$ Therefore, the correct answer is E. I hope this explanation may help you. I'm available if you'd like a follow-up. Regards. _________________ 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 • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

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