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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 A factory has three types of machines, each of which works tagged by: AAPL This topic has 7 expert replies and 0 member replies Top Member A factory has three types of machines, each of which works Timer 00:00 Your Answer A B C D E Global Stats Difficult Veritas Prep A factory has three types of machines, each of which works at its own constant rate. If 7 Machine As and 11 Machine Bs can produce 250 widgets per hour, and if 8 Machine As and 22 Machine Cs can produce 600 widgets per hour, how many widgets could one machine A, one Machine B, and one Machine C produce in one 8-hour day? A. 400 B. 475 C. 550 D. 625 E. 700 OA A GMAT/MBA Expert GMAT Instructor Joined 04 Dec 2012 Posted: 2094 messages Followed by: 238 members Upvotes: 1443 At first, it might seem as if we don't have enough information to solve. We have 3 unknowns (the rates of Machines A, B, and C), but only 2 equations. Since this is Problem Solving and not Data Sufficiency, though, (and there is no "cannot be determined" answer) there must be some way to solve. Let's let A = the rate of Machine A, and so on. Construct equations for (number of machines)(hourly rate of machines) = (output per hour per machine) 7 Machine As and 11 Machine Bs can produce 250 widgets per hour --> 7A + 11B = 250 8 Machine As and 22 Machine Cs can produce 600 widgets per hour --> 8A + 22C = 600 As stated before, we have 2 equations for 3 variables, and it looks like we're stuck. But since it's PS, there must be a way to combine them! Simplify the 2nd equation, then combine it with the 1st: 4A + 11C = 300 7A + 11B = 250 __________________ 11A + 11B + 11C = 550 --> A + B + C = 50 If we had one of each machine, the 3 together would produce 50 widgets per hour. We don't have to know what each machine does individually. Since the question asks how many widgets can be produced by these 3 in 8 hrs, (50)(8) = 400. The answer is A. _________________ 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 GMAT Instructor Joined 25 May 2010 Posted: 15353 messages Followed by: 1864 members Upvotes: 13060 GMAT Score: 790 AAPL wrote: Veritas Prep A factory has three types of machines, each of which works at its own constant rate. If 7 Machine As and 11 Machine Bs can produce 250 widgets per hour, and if 8 Machine As and 22 Machine Cs can produce 600 widgets per hour, how many widgets could one machine A, one Machine B, and one Machine C produce in one 8-hour day? A. 400 B. 475 C. 550 D. 625 E. 700 OA A Rates can be ADDED TOGETHER. 7 Machine As and 11 Machine Bs can produce 250 widgets per hour. 7A + 11B = 250 8 Machine As and 22 Machine Cs can produce 600 widgets per hour. 8A + 22C = 600 4A + 11C = 300 Adding together 7A + 11B = 250 and 4A + 11C = 300, we get: 11A + 11B + 11C = 550 A + B + C = 50 Since A+B+C together produce 50 widgets per hour, the number of widgets produced by A+B+C in an 8-hour day = 50*8 = 400. The correct answer is A. _________________ 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 Oct 2010 Posted: 1449 messages Followed by: 32 members Upvotes: 59 Hi there! I would like to suggest that we all avoid posting solutions that are IDENTICAL to solutions that were posted in the very same topic. This is not only in respect for our colleagues but also for the benefit of the whole BTG community. On this matter, if I violate this "rule" I kindly ask anyone who felt uncomfortable to complain. I apologise in advance, by the way. Thank you for your understanding. Regards, Fabio. _________________ Fabio Skilnik :: GMATH method creator ( Math for the GMAT) English-speakers :: https://www.gmath.net Portuguese-speakers :: https://www.gmath.com.br GMAT/MBA Expert GMAT Instructor Joined 25 May 2010 Posted: 15353 messages Followed by: 1864 members Upvotes: 13060 GMAT Score: 790 fskilnik@GMATH wrote: Hi there! I would like to suggest that we all avoid posting solutions that are IDENTICAL to solutions that were posted in the very same topic. This is not only in respect for our colleagues but also for the benefit of the whole BTG community. On this matter, if I violate this "rule" I kindly ask anyone who felt uncomfortable to complain. I apologise in advance, by the way. Thank you for your understanding. Regards, Fabio. In many cases, similar or identical solutions are posted when two experts respond at virtually the same time, with the result that the second poster is not aware of the first. The time stamps for the two solutions here indicate that both solutions were posted at 11:45am. _________________ 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 Last edited by GMATGuruNY on Tue Oct 23, 2018 12:09 pm; edited 1 time in total 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 Dec 2012 Posted: 2094 messages Followed by: 238 members Upvotes: 1443 Fabio, I definitely agree with your sentiment generally! But Mitch & I have worked side by side for years, with much mutual respect (I'm assuming!). I've never known him to knowingly step on anyone's toes. I'm sure we've all had the experience of someone else posting while we were in the middle of writing, being none the wiser. _________________ 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 GMAT Instructor Joined 09 Oct 2010 Posted: 1449 messages Followed by: 32 members Upvotes: 59 First of all, I owe you my apologies, Mitch. (I simply did not see the time stamps. My fault.) Very elegant observations, Ceilidh! I have already shown my respect to MitchÂ´s competence in the near past, by the way: https://www.beatthegmat.com/agatha-christiea-acute-s-escalator-t303990.html Anyway, you all have my compromise on this matter and I hope (and believe) you all agree to adopt the same posture. Regards, Fabio. _________________ Fabio Skilnik :: GMATH method creator ( Math for the GMAT) English-speakers :: https://www.gmath.net Portuguese-speakers :: https://www.gmath.com.br GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2801 messages Followed by: 18 members Upvotes: 43 AAPL wrote: Veritas Prep A factory has three types of machines, each of which works at its own constant rate. If 7 Machine As and 11 Machine Bs can produce 250 widgets per hour, and if 8 Machine As and 22 Machine Cs can produce 600 widgets per hour, how many widgets could one machine A, one Machine B, and one Machine C produce in one 8-hour day? A. 400 B. 475 C. 550 D. 625 E. 700 Letting a, b, and c be the hourly output of Machines a, b, and c, respectively, we can create the equations: 7a + 11b = 250 And 8a + 22c = 600 Multiplying the first equation by 2, we have: 14a + 22b = 500 Adding the two equations together we have: 22a + 22b + 22c = 1100 a + b + c = 50 So in 8 hours the 3 machines can produce 400 widgets. Answer: A _________________ Scott Woodbury-Stewart Founder and CEO scott@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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