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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 ## The aerth travels around the sun at a speed of approximately tagged by: AAPL ##### This topic has 3 expert replies and 1 member reply ### Top Member ## The aerth travels around the sun at a speed of approximately ## Timer 00:00 ## Your Answer A B C D E ## Global Stats Difficult GMAT Prep The earth travels around the sun at a speed of approximately 18.5 miles per second. The approximate is how many miles per hour? A. 1,080 B. 1,160 C. 64,800 D. 66,600 E. 3,996,000 OA D. ### GMAT/MBA Expert GMAT Instructor Joined 09 Oct 2010 Posted: 1295 messages Followed by: 29 members Upvotes: 59 AAPL wrote: GMAT Prep The earth travels around the sun at a speed of approximately 18.5 miles per second. The approximate is how many miles per hour? A. 1,080 B. 1,160 C. 64,800 D. 66,600 E. 3,996,000 Trivial application of the UNITS CONTROL, one of our method´s most powerful techniques! $?\,\,\, = \,\,\,\frac{{18.5\,\,{\text{miles}}}}{{1\,\,{\text{s}}}}\,\,\,\left( {\frac{{60\,\,{\text{s}}}}{{1\,\,{\text{minute}}}}\,\,\begin{array}{*{20}{c}} \nearrow \\ \nearrow \end{array}} \right)\,\,\,\,\left( {\frac{{60\,\,{\text{minutes}}}}{{1\,\,{\text{h}}}}\,\,\begin{array}{*{20}{c}} \nearrow \\ \nearrow \end{array}} \right)\,\,\,\, = \,\,\frac{{37}}{2} \cdot 36 \cdot 100 = 37 \cdot 18 \cdot 100 = 66,600\,\,\,\left[ {{\text{mph}}} \right]$ Obs.: arrows indicate licit converters. This solution follows the notations and rationale taught in the GMATH method. Regards, fskilnik. _________________ Fabio Skilnik :: GMATH method creator ( Math for the GMAT) English-speakers :: https://www.gmath.net Portuguese-speakers :: https://www.gmath.com.br ### Top Member Legendary Member Joined 29 Oct 2017 Posted: 783 messages Followed by: 4 members This is a classic case of approximations as the options are too widespread. 18.5 mps to 18.5 mph with 1 h = 3600 seconds. Thus 18.5 mps = 18.5*3600 = a bit more than 18*3600 = a bit more than 18*18*200 = a bit more than 324*2*100 = a bit more than 64800 . So eliminate C and mark D is the correct answer. You need to remember squares from 1 to 20 for GMAT. Regards! ### GMAT/MBA Expert GMAT Instructor Joined 08 Dec 2008 Posted: 12663 messages Followed by: 1246 members Upvotes: 5254 GMAT Score: 770 Another way to deal with calculating (18.5)(3600) is to use the answer choices to our advantage. First off, there's a nice rule that says: AB = (2A)(0.5B) This strategy (which is covered in this video: https://www.gmatprepnow.com/module/general-gmat-strategies/video/1113) can sometimes save us some calculations. When we apply the rule, (18.5)(3600) = (37)(1800) [I doubled 18.5 to get 37, and I halved 3600 to get 1800 ] = (37)(18)(100) = (----6)(100) [We know that the units digit of 37 x 18 must be 6, since 7 x 8 = 56] = ---600 [some number that ends with 600] Check the answer choices.... A. 1,080 B. 1,160 C. 64,800 D. 66,600 BINGO!! E. 3,996,000 Cheers, Brent _________________ Brent Hanneson – Creator of GMATPrepNow.com Use our video course along with Sign up for our free Question of the Day emails And check out all of our free resources GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMAT’s FREE 60-Day Study Guide and reach your target score in 2 months! ### GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2012 messages Followed by: 15 members Upvotes: 43 AAPL wrote: GMAT Prep The earth travels around the sun at a speed of approximately 18.5 miles per second. The approximate is how many miles per hour? A. 1,080 B. 1,160 C. 64,800 D. 66,600 E. 3,996,000 Since 1 second = 1/3600 hours, the rate in miles per hour is: 18.5/(1/3600) = 18.5 x 3600 = 66,600 Answer: D _________________ Scott Woodbury-Stewart Founder and CEO • 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 • 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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