GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 12 Nov 2018, 10:29

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

## Events & Promotions

###### Events & Promotions in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
• ### Essential GMAT Time-Management Hacks

November 14, 2018

November 14, 2018

08:00 PM MST

09:00 PM MST

Join the webinar and learn time-management tactics that will guarantee you answer all questions, in all sections, on time. Save your spot today! Nov. 14th at 7 PM PST

# A transcontinental jet travels at a rate of x – 100 mph with a headwin

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 50543
A transcontinental jet travels at a rate of x – 100 mph with a headwin  [#permalink]

### Show Tags

28 Jul 2017, 07:43
00:00

Difficulty:

85% (hard)

Question Stats:

53% (03:22) correct 47% (03:22) wrong based on 84 sessions

### HideShow timer Statistics

A transcontinental jet travels at a rate of x – 100 mph with a headwind and x + 100 mph with a tailwind between Wavetown and Urbanio, two cities 3,200 miles apart. If it takes the jet 2 hr 40 minutes longer to complete the trip with a headwind, then what is the jet’s rate flying with a tailwind?

(A) 500

(B) 540

(C) 600

(D) 720

(E) Cannot be determined by the information given.

_________________
Manager
Joined: 02 Nov 2015
Posts: 166
GMAT 1: 640 Q49 V29
Re: A transcontinental jet travels at a rate of x – 100 mph with a headwin  [#permalink]

### Show Tags

28 Jul 2017, 10:50
2
1
Time to cover the distance with wind is 3200/(x+100)
And time taken to cover against and is 3200/(x-100).
Now the stem says it takes 2 hours and 40 mins more to complete the trip with headwind. So 2 hours and 40 in turn to 8/3 hours.
So the equation is
[3200/(x-100)] -[3200/(x+100)] = 8/3...
Solving we get x=500 which is the speed of jet ad 100 is the speed of wind.
Combined it's 600.

Sent from my Lenovo TAB S8-50LC using GMAT Club Forum mobile app
Senior SC Moderator
Joined: 22 May 2016
Posts: 2082
A transcontinental jet travels at a rate of x – 100 mph with a headwin  [#permalink]

### Show Tags

28 Jul 2017, 18:38
Bunuel wrote:
A transcontinental jet travels at a rate of x – 100 mph with a headwind and x + 100 mph with a tailwind between Wavetown and Urbanio, two cities 3,200 miles apart. If it takes the jet 2 hr 40 minutes longer to complete the trip with a headwind, then what is the jet’s rate flying with a tailwind?

(A) 500

(B) 540

(C) 600

(D) 720

(E) Cannot be determined by the information given.

I backsolved. I was taking too long to find the equations.

Difference in time should be 2 hours 40 minutes = 2$$\frac{2}{3}$$ = $$\frac{8}{3}$$ hours

1. Find tailwind time from $$D/r$$

TW time is $$\frac{3200}{600}$$ = $$\frac{32}{6}$$ = $$\frac{16}{3}$$ hours

Tailwind rate is 500 = x + 100, x = 400
Headwind rate is x - 100 = 300

HW time is $$\frac{3200}{400}$$ = $$\frac{32}{4}$$ = 8 hours

4. Difference in time?

(8 -$$\frac{16}{3}$$)=($$\frac{24- 18}{3}$$) = $$\frac{8}{3}$$ hours. Correct.

Director
Joined: 13 Mar 2017
Posts: 626
Location: India
Concentration: General Management, Entrepreneurship
GPA: 3.8
WE: Engineering (Energy and Utilities)
Re: A transcontinental jet travels at a rate of x – 100 mph with a headwin  [#permalink]

### Show Tags

28 Jul 2017, 22:03
1
Bunuel wrote:
A transcontinental jet travels at a rate of x – 100 mph with a headwind and x + 100 mph with a tailwind between Wavetown and Urbanio, two cities 3,200 miles apart. If it takes the jet 2 hr 40 minutes longer to complete the trip with a headwind, then what is the jet’s rate flying with a tailwind?

(A) 500

(B) 540

(C) 600

(D) 720

(E) Cannot be determined by the information given.

Time difference between headwind and tailwind = 2 hr 40 min = 2 + 40/60 = 8/3 hour
So, 3200/(x-100) - 3200/(x+100) = 8/3
-> 400 * 200 / (x^2-10000) = 1/3
-> 240000 = x^2 -10000
x^2 = 250000
x = 500

So, Jet's rate flying with a tailwind = 500+ 100 = 600 mph

_________________

CAT 2017 99th percentiler : VA 97.27 | DI-LR 96.84 | QA 98.04 | OA 98.95
UPSC Aspirants : Get my app UPSC Important News Reader from Play store.

MBA Social Network : WebMaggu

Appreciate by Clicking +1 Kudos ( Lets be more generous friends.)

What I believe is : "Nothing is Impossible, Even Impossible says I'm Possible" : "Stay Hungry, Stay Foolish".

Non-Human User
Joined: 09 Sep 2013
Posts: 8737
Re: A transcontinental jet travels at a rate of x – 100 mph with a headwin  [#permalink]

### Show Tags

07 Sep 2018, 06:21
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: A transcontinental jet travels at a rate of x – 100 mph with a headwin &nbs [#permalink] 07 Sep 2018, 06:21
Display posts from previous: Sort by