Jul 16 03:00 PM PDT  04:00 PM PDT Join a free live webinar and find out which skills will get you to the top, and what you can do to develop them. Save your spot today! Tuesday, July 16th at 3 pm PST Jul 16 08:00 PM EDT  09:00 PM EDT Strategies and techniques for approaching featured GMAT topics. Tuesday, July 16th at 8 pm EDT Jul 19 08:00 AM PDT  09:00 AM PDT The Competition Continues  Game of Timers is a teambased competition based on solving GMAT questions to win epic prizes! Starting July 1st, compete to win prep materials while studying for GMAT! Registration is Open! Ends July 26th Jul 20 07:00 AM PDT  09:00 AM PDT Attend this webinar and master GMAT SC in 10 days by learning how meaning and logic can help you tackle 700+ level SC questions with ease. Jul 21 07:00 AM PDT  09:00 AM PDT Attend this webinar to learn a structured approach to solve 700+ Number Properties question in less than 2 minutes
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 56244

Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 01:52
Question Stats:
70% (02:21) correct 30% (02:33) wrong based on 462 sessions
HideShow timer Statistics
Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip? A. 40 B. 42.5 C. 44 D. 50 E. 52.5 Kudos for a correct solution.
Official Answer and Stats are available only to registered users. Register/ Login.
_________________



Director
Joined: 20 Feb 2015
Posts: 790
Concentration: Strategy, General Management

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 03:51
Time Taken for the first part of the journey= 8/40 = 1/5 hr=12 min
Idle time =10 min
Time Taken for the second part of the journey= 20/60= 1/3 hr =20 min
Total time taken =42 min = 7/10 hr
Total distance = 28 miles
therefore avg speed (28/7)*10 =40 miles per hour
> : A



CEO
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2959
Location: India
GMAT: INSIGHT
WE: Education (Education)

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 04:06
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5
Kudos for a correct solution. Total Time taken by jerry = (8/40)*60 Minutes + 10 Minutes + (20/60)*60 Minutes = 42 Minutes Average Speed = Total Distance / Total Time = (8+20) miles / (42/60)Hours = 28*60 / 42 = 40 Miles per hour Answer: option A
_________________
Prosper!!!GMATinsightBhoopendra Singh and Dr.Sushma Jha email: info@GMATinsight.com I Call us : +919999687183 / 9891333772 Online OneonOne Skype based classes and Classroom Coaching in South and West Delhihttp://www.GMATinsight.com/testimonials.htmlACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION



Manager
Joined: 14 Mar 2014
Posts: 145

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 04:18
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5
Kudos for a correct solution. IMO: A Avg speed = \(\frac{Total distance}{Total time}\) Total distance = 20+8 = 28 miles Total time = t1+t2+t3 t1= 8 miles at an average speed of 40 miles per hour ==> 8/40 = 1/5 hr t2 = 10 minutes idle time = 10/60 = 1/6 hr t3 = 20 miles at an average speed of 60 miles per hour ==> 20/60 = 1/3 hr Total time = 1/5 + 1/6 + 1/3 = 7/10 Avg speed = \(\frac{28*10}{7}\) = 40 miles per hr
_________________
I'm happy, if I make math for you slightly clearer And yes, I like kudos ¯\_(ツ)_/¯



Intern
Status: My heart can feel, my brain can grasp, I'm indomitable.
Affiliations: Educator
Joined: 16 Oct 2012
Posts: 39
Location: Bangladesh
WE: Social Work (Education)

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 04:38
total distance = 8+20 =28 miles time = distance/ speed total time = 8/40 (to go 1st 8 miles) + 10/60 (break) + 20/ 60 (to go 2nd 60 miles) = 7/10 hours average speed = total distance / total time = 28 /(7/10) =40 miles per hour ans: A
_________________
please press "+1 Kudos" if useful



Senior Manager
Joined: 28 Jun 2015
Posts: 286
Concentration: Finance
GPA: 3.5

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 05:01
Total distance traveled = \(8+20 = 28\). Total time taken = \(\frac{60*8}{40} + 10 + 20 = 12 + 10 + 20 = 42\) mins. Average speed = \(\frac{28*60}{42} = 40\) mph. Ans (A).
_________________
I used to think the brain was the most important organ. Then I thought, look what’s telling me that.



Intern
Joined: 01 Jul 2014
Posts: 25
Location: India
GPA: 3.2

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 Jul 2015, 06:45
Average Speed = Total Distance / Total Time
Total distance = 8+20 = 28 miles
Total time = ((8/40)*60) + 10 + ((20/60)*60) = 42 mins = 42/60 hrs
Average speed = (28/42)*60 = 40 miles per hr



Math Expert
Joined: 02 Sep 2009
Posts: 56244

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
17 Aug 2015, 09:39
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5
Kudos for a correct solution. 800score Official Solution:Since Rate = Distance/Time, the average rate at which Jerry travels over a certain distance can be found by dividing the total distance of the trip by the total time for the trip. Let’s find the times for the various portions of the trip using the formula Time = Distance / Rate: Traveling 8 miles at a speed of 40 miles per hour takes 8/40 = 1/5 hour. Similarly, traveling 20 miles at 60 miles per hour takes 20/60 = 1/3 hour. The 10 minutes he was stopped is equal to 1/6 of an hour. Adding all these times together gives us the total time: Total time = 1/5 + 1/3 + 1/6 = 6/30 +10/30 + 5/30 = 21/30 = 7/10 hour. The total distance traveled is 28 miles. Therefore, the average speed is: = 28 / (7/10) = 28 × (10/7) = 40 miles per hour. The correct answer is choice (A).
_________________



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 6923
Location: United States (CA)

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
28 May 2018, 19:49
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5 Using the formula Average = total distance/total time, we have: Average = 28/(8/40 + 1/6 + 20/60) Average = 28/(1/5 + 1/6 + 1/3) Average = 28/(6/30 + 5/30 + 10/30) Average = 28/(21/30) = (30 x 28)/21 = (30 x 28)/(3 x 7) = 10 x 4 = 40. Answer: A
_________________
5star rated online GMAT quant self study course See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews If you find one of my posts helpful, please take a moment to click on the "Kudos" button.



Manager
Joined: 16 May 2017
Posts: 51
GPA: 3.8
WE: Medicine and Health (Health Care)

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
20 Oct 2018, 07:42
Total time travelled by Jerry= 60*8/40+10+60*20/60= 12+10+20= 42 mins Total distance travelled by Jerry= 8+20= 28 miles Average speed= total distance/total time= 28/42= 2/3 miles per min= 2*60/3= 40 miles per hour.
Ans (A)



Intern
Joined: 06 Jun 2017
Posts: 5

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
29 Oct 2018, 14:24
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5
Kudos for a correct solution. Formula: D = RT Given: \(D_1 = 8 miles\) \(R_1 = 40 mph\) \(T_1 = \frac{{D_1}}{{R_1}} = \frac{{8 miles}}{{40 mph}} = \frac{1}{5}hour\) Convert minutes to hours because the final answer needs to be in miles per hour\(T_2 = 10 minutes = \frac{1}{6}hour\) \(D_3 = 20 miles\) \(R_3 = 60 mph\) \(T_3 = \frac{{D_3}}{{R_3}} = \frac{{20 miles}}{{60 mph}} = \frac{1}{3}hour\) Total distance = 8 miles + 20 miles = 28 miles Solve: 1. Solve for overall rate using D = RT 2. In order to get total time, find the sum of all provided times: \(T_1 + T_2 + T_3 = \frac{1}{5}hour + \frac{1}{6}hour + \frac{1}{3}hour = (7/10)hour\) 3. \(\frac{D}{T} = \frac{{28 miles}}{(7/10)hour}\) = 40 mph



Director
Joined: 19 Oct 2013
Posts: 525
Location: Kuwait
GPA: 3.2
WE: Engineering (Real Estate)

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
29 Oct 2018, 15:51
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5
Kudos for a correct solution. T1 = 8/40 = 1/5 Time stopped = 10 mins = 1/6 T2 = 20/60 = 1/3 Total time = 1/5 + 1/3 + 1/6 = 6 + 10 + 5 = 21/30 = 7/10 Avg speed = total distance/total time = 20 + 8 = 28/(7/10) = (28*10)/7 = 4*10 = 40 Answer choice A Posted from my mobile device



VP
Joined: 09 Mar 2018
Posts: 1002
Location: India

Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
Show Tags
25 Jan 2019, 03:41
Bunuel wrote: Jerry travels 8 miles at an average speed of 40 miles per hour, stops for 10 minutes, and then travels another 20 miles at an average speed of 60 miles per hour. What is Jerry’s average speed, in miles per hour, for this trip?
A. 40 B. 42.5 C. 44 D. 50 E. 52.5
Kudos for a correct solution. Average Speed = Total Distance / Total Time Total Distance = 28 Total Time = 8/40 + 1/6 + 20/60 = 21/30 Average Speed = 28 * 30 / 21 = 40 miles/ hr A
_________________
If you notice any discrepancy in my reasoning, please let me know. Lets improve together.
Quote which i can relate to. Many of life's failures happen with people who do not realize how close they were to success when they gave up.




Re: Jerry travels 8 miles at an average speed of 40 miles per hour, stops
[#permalink]
25 Jan 2019, 03:41






