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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 ## John traveled the entire 60 miles trip. If he did the... tagged by: AAPL ##### This topic has 4 expert replies and 3 member replies ### Top Member ## John traveled the entire 60 miles trip. If he did the... John traveled the entire 60 miles tirp. if he did the first 12 miles of a constant rate 24 miles per hour and the remaining trip of a constant rate 48 miles per hour, what is the his average speed, in miles per hour? A. 20 mph B. 24 mph C. 30 mph D. 32 mph E. 40 mph The OA is E. Is there a strategic approach to this PS question? Can any experts help, please? I know that average speed will be, total distance / total time, but i don't know how can I do or how can I solve this question. I need your help. Thanks! ### GMAT/MBA Expert Legendary Member Joined 14 Jan 2015 Posted: 2667 messages Followed by: 122 members Upvotes: 1153 GMAT Score: 770 AAPL wrote: John traveled the entire 60 miles tirp. if he did the first 12 miles of a constant rate 24 miles per hour and the remaining trip of a constant rate 48 miles per hour, what is the his average speed, in miles per hour? A. 20 mph B. 24 mph C. 30 mph D. 32 mph E. 40 mph The OA is E. Is there a strategic approach to this PS question? Can any experts help, please? I know that average speed will be, total distance / total time, but i don't know how can I do or how can I solve this question. I need your help. Thanks! Well, you could do the math. First part of trip: it'll take 1/2 hour to go 12 miles at 24 mph. Second part of trip: There are 60-12 = 48miles remaining. It'll take 1 hour to cover those 48 miles at 48mph. Total distance:60 Total time: 1/2 + 1 = 1/5 hours Avg rate: 60/1.5 = 40 mph. The answer is E _________________ Veritas Prep | GMAT Instructor Veritas Prep Reviews Save$100 off any live Veritas Prep GMAT Course

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AAPL wrote:
John traveled the entire 60 miles tirp. if he did the first 12 miles of a constant rate 24 miles per hour and the remaining trip of a constant rate 48 miles per hour, what is the his average speed, in miles per hour?

A. 20 mph
B. 24 mph
C. 30 mph
D. 32 mph
E. 40 mph

The OA is E.

Is there a strategic approach to this PS question? Can any experts help, please?

I know that average speed will be, total distance / total time, but i don't know how can I do or how can I solve this question. I need your help. Thanks!
But you can see that if John spent the same amount of time traveling at 24mph and at 48mph, he'd have traveled at (24 + 48)/2 = 72/2 = 36 mph. So long as you see that he spent more time traveling at 48mph than at 24 mph, we know his average would have been pulled towards the faster speed, and thus that average would to be greater than 36 mph. Only E works.

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Save $100 off any live Veritas Prep GMAT Course Enroll in a Veritas Prep GMAT class completely for FREE. Wondering if a GMAT course is right for you? Attend the first class session of an actual GMAT course, either in-person or live online, and see for yourself why so many students choose to work with Veritas Prep. Find a class now! Senior | Next Rank: 100 Posts Joined 15 Jan 2018 Posted: 83 messages Using speed = distance/time, we get time = speed over distance, so total time, T = t1 + t2 = 12/24 + 48/48 = 1.5 Average speed = D/T = 60/1.5 = 40 Newbie | Next Rank: 10 Posts Joined 15 Jan 2018 Posted: 1 messages AAPL wrote: John traveled the entire 60 miles tirp. if he did the first 12 miles of a constant rate 24 miles per hour and the remaining trip of a constant rate 48 miles per hour, what is the his average speed, in miles per hour? A. 20 mph B. 24 mph C. 30 mph D. 32 mph E. 40 mph The OA is E. Is there a strategic approach to this PS question? Can any experts help, please? I know that average speed will be, total distance / total time, but i don't know how can I do or how can I solve this question. I need your help. Thanks! 12 miles at 24 mph = 30 mins. 48 miles at 48 mph = 60 mins. Total time taken = 30+60 = 90 mins. Total distance = 60 miles. Average speed = (60/90) * 60 = 40 mph. ### GMAT/MBA Expert Elite Legendary Member Joined 23 Jun 2013 Posted: 10197 messages Followed by: 496 members Upvotes: 2867 GMAT Score: 800 Hi AAPL, We're told that John tool a 60 miles trip; the first 12 miles of a constant rate 24 miles per hour and the remaining distance at a constant rate 48 miles per hour. We're asked for the average speed, in miles per hour, for the entire trip. To answer this question, you might find it easiest to break the calculation down into 'pieces.' 1st part of the trip: 12 miles at 24 miles/hour.... Distance = (Rate)(Time) 12 miles = (24 mi/hour)(T) 12/24 = T T = 1/2 hour 2nd part of the trip: 48 miles at 48 miles/hour.... Distance = (Rate)(Time) 48 miles = (48 mi/hour)(T) 48/48 = T T = 1 hour Total Distance = 60 miles Total Time = 1.5 hours Total Distance = (Av. Speed)(Total Time) 60 miles = (X)(1.5 hours) 60/1.5 = X 120/3 = X X = 40 miles per hour Final Answer: E GMAT assassins aren't born, they're made, Rich _________________ Contact Rich at Rich.C@empowergmat.com ### GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2791 messages Followed by: 18 members Upvotes: 43 AAPL wrote: John traveled the entire 60 miles tirp. if he did the first 12 miles of a constant rate 24 miles per hour and the remaining trip of a constant rate 48 miles per hour, what is the his average speed, in miles per hour? A. 20 mph B. 24 mph C. 30 mph D. 32 mph E. 40 mph We can use the formula: Average speed = (total distance/total time) The time for the first 12 miles was 12/24 = 0.5 hour. The time for the remaining 48 miles was 48/48 = 1 hour. Thus: Average speed = 60/1.5 = 40 mph Answer: E _________________ 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 Master | Next Rank: 500 Posts Joined 20 Apr 2017 Posted: 228 messages Followed by: 3 members Upvotes: 32 GMAT Score: 770 If you're doing a lot of math, chances are you're doing something wrong. The Quant part of the GMAT isn't a math test -- it's a test of reasoning ability. If you travel half of the trip at 24 mph and the other half at 48 mph, then you will average 36 mph. However, John only did 12 miles of 60 miles at the slow speed. Granted, it's about the TIME spent not the DISTANCE, but even so, it's obvious that the answer must be greater than 36 mph. There is only one choice that is greater than 36 mph, and that's (E). Next problem! _________________ Elias Latour Verbal Specialist @ ApexGMAT blog.apexgmat.com +1 (646) 736-7622 • 1 Hour Free BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • Free Trial & Practice Exam BEAT THE GMAT EXCLUSIVE 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 Practice Test & Review How would you score if you took the GMAT 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 GMAT Exam Know how you'd score today for$0

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