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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 ## There are 7 players in a bowling team with an average... tagged by: swerve ##### This topic has 5 expert replies and 0 member replies ### Top Member ## There are 7 players in a bowling team with an average... There are 7 players in a bowling team with an average weight of 85kg. If two new players join the team, one weight 110 kg and the second weight 60 kg, what will be the new average weight? A. 75 kg B. 80 kg C. 85 kg D. 90 kg E. 92 kg The OA is C. Please, can any expert explain this PS question for me? I tried to solve it of the following way but I'm not sure, Can I say that, $$N_{avg}=\frac{85+\left(\frac{110+60}{2}\right)}{2}=85\ kg$$ I need your help. Thanks. ### GMAT/MBA Expert GMAT Instructor Joined 04 Dec 2012 Posted: 2094 messages Followed by: 239 members Upvotes: 1443 Top Reply EconomistGMATTutor wrote: Hi swerve, Let's take a look at your question. We have three numbers, one is 85, average of 7 numbers and other two are 110 and 60. We can find average of these three numbers as: $$Average\ =\ \frac{85+110+60}{3}=\frac{255}{3}=85$$ Therefore, option B is correct. Hope it helps. I am available if you's like any follow up. EconomistGMAT - You got the right answer, but your math was faulty here. It is only because the two additional numbers average to 85 that this works out. Imagine instead that the two new weights were 105 and 110. We could not simply take (85 + 105 + 110)/3 and get 100. There were 7 players with a weight of 85, so there would be 9 players in total: (7(85) + 100 + 110)/9 = 90. This is weighted toward the 7 players with a lower average weight. On this actual problem, Mitch and Rich rightly pointed out that because the 2 new weights average to the old average of 85, we don't have to do any additional math. If we didn't notice this, though, and wanted to do the math, the correct formula would be: $$Average\ =\ \frac{7*85+110+60}{9}=85$$ _________________ Ceilidh Erickson Manhattan Prep GMAT & GRE instructor EdM in Mind, Brain, and Education Harvard Graduate School of Education Manhattan Prep instructors all have 99th+ percentile scores and expert teaching experience. Sign up for a FREE TRIAL, and learn why we have the highest ratings in the GMAT industry! Free Manhattan Prep online events - The first class of every online Manhattan Prep course is free. Classes start every week. ### GMAT/MBA Expert Elite Legendary Member Joined 23 Jun 2013 Posted: 10197 messages Followed by: 497 members Upvotes: 2867 GMAT Score: 800 Top Reply Hi swerve, We're told that 7 players on a bowling team have an average weight of 85kg and that two new players join the team (one weighing 110 kg and the other weighing 60 kg). We're asked for the average weight of the 'new' team. This question be solved in a couple of different ways. Here's how you can solve it without doing too much math - focusing instead on the 'net effect' that the two 'new' weights would have on the average... 110kg is 25kg "more" than the current average (re: 85kg). 60kg is 25kg "less" than the current average (re: 85kg). Thus, the 'increase' from the heavier person is 'cancelled out' by the 'decrease' from the lighter person... and the average weight of the group would stay the SAME. Final Answer: C GMAT assassins aren't born, they're made, Rich _________________ Contact Rich at Rich.C@empowergmat.com ### GMAT/MBA Expert GMAT Instructor Joined 04 Oct 2017 Posted: 551 messages Followed by: 11 members Upvotes: 180 Quote: There are 7 players in a bowling team with an average weight of 85kg. If two new players join the team, one weight 110 kg and the second weight 60 kg, what will be the new average weight? A. 75 kg B. 80 kg C. 85 kg D. 90 kg E. 92 kg The OA is C. Please, can any expert explain this PS question for me? I tried to solve it of the following way but I'm not sure, Hi swerve, Let's take a look at your question. We have three numbers, one is 85, average of 7 numbers and other two are 110 and 60. We can find average of these three numbers as: $$Average\ =\ \frac{85+110+60}{3}=\frac{255}{3}=85$$ Therefore, option B is correct. Hope it helps. I am available if you's 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. ### GMAT/MBA Expert GMAT Instructor Joined 25 May 2010 Posted: 15383 messages Followed by: 1872 members Upvotes: 13060 GMAT Score: 790 swerve wrote: There are 7 players in a bowling team with an average weight of 85kg. If two new players join the team, one weight 110 kg and the second weight 60 kg, what will be the new average weight? A. 75 kg B. 80 kg C. 85 kg D. 90 kg E. 92 kg Average weight of the 7 original players = 85. Average weight of the 2 new players = (110+60)/2 = 85. Since the two groups have the same average weight -- 85 -- the MIXTURE of the two groups must also have an average weight of 85. 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. ### GMAT/MBA Expert GMAT Instructor Joined 09 Apr 2015 Posted: 1465 messages Followed by: 19 members Upvotes: 39 swerve wrote: There are 7 players in a bowling team with an average weight of 85kg. If two new players join the team, one weight 110 kg and the second weight 60 kg, what will be the new average weight? A. 75 kg B. 80 kg C. 85 kg D. 90 kg E. 92 kg The sum of the weights of the 7 bowlers is 7 x 85 = 595. If we add in two new players, the new sum is 595 + 110 + 60 = 765. So the new average is 765/9 = 85 Alternate Solution: When looking at the two new weights, we could have noticed that one weight is 25 greater and the other is 25 less than the average, thus creating no change in the average of the weights of the members of the team. Answer: C _________________ Jeffrey Miller Head of GMAT Instruction jeff@targettestprep.com See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews • Free Trial & Practice Exam BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

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