It is currently 23 Mar 2018, 21:14

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 June
Open Detailed Calendar

While driving from A-ville to B-town, Harriet drove at a constant spee

Author Message
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 44419
While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

19 Feb 2015, 09:55
Expert's post
5
This post was
BOOKMARKED
00:00

Difficulty:

45% (medium)

Question Stats:

74% (03:02) correct 26% (02:34) wrong based on 321 sessions

HideShow timer Statistics

While driving from A-ville to B-town, Harriet drove at a constant speed of 115 kilometers per hour. Upon arriving in B-town, Harriet immediately turned and drove back to A-ville at a constant speed of 135 kilometers per hour. If the entire trip took 5 hours, how many minutes did it take Harriet to drive from A-ville to B-town?

A. 138
B. 148
C. 150
D. 162
E. 168

Kudos for a correct solution.
[Reveal] Spoiler: OA

_________________
Intern
Joined: 19 Feb 2015
Posts: 14
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

19 Feb 2015, 11:00
2
KUDOS
X = Time from A to B
Y = Time from B to A
X+Y=5 hrs total travel time
115X=135Y since the distances are the same

X+Y=5 => 135X+135Y=675
115X=135Y => 115X-135Y=0
Combined you get
250X=675 hrs
X=2.7 hrs * 60 mins/hr= 162
Retired Moderator
Status: I Declare War!!!
Joined: 02 Apr 2014
Posts: 250
Location: United States
Concentration: Finance, Economics
GMAT Date: 03-18-2015
WE: Asset Management (Investment Banking)
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

19 Feb 2015, 11:27
3
KUDOS
Its D.
Here it goes:
Distance will be same both sides... hence total distance will D+D= 2D
Total time given+ 5hrs
Speed per side also given.. 115km/ph and 135 km/ph
Speed= Distanct/Time
D/s1 + D/s2= total time
(d/115) + (d/135) = 5
solving it D comes to 621 km
Hence each side is D/2 : 621/2 = 310.5 km
Time for first journey is 310.5/115 which is 162 mins
Thanks

Kudos please if my solution is correct!
Manager
Joined: 18 Aug 2014
Posts: 128
Location: Hong Kong
Schools: Mannheim
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

19 Feb 2015, 12:49
1
KUDOS
Celestial09 wrote:
Its D.
Here it goes:
Distance will be same both sides... hence total distance will D+D= 2D
Total time given+ 5hrs
Speed per side also given.. 115km/ph and 135 km/ph
Speed= Distanct/Time
D/s1 + D/s2= total time
(d/115) + (d/135) = 5
solving it D comes to 621 km
Hence each side is D/2 : 621/2 = 310.5 km
Time for first journey is 310.5/115 which is 162 mins
Thanks

Kudos please if my solution is correct!

Hello,

I have struggles coming from (D/115) + (D/135) = 5
to D = 621

could you explain the calculation steps ?
Retired Moderator
Status: I Declare War!!!
Joined: 02 Apr 2014
Posts: 250
Location: United States
Concentration: Finance, Economics
GMAT Date: 03-18-2015
WE: Asset Management (Investment Banking)
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

19 Feb 2015, 13:06
1
KUDOS
Hello!
(d/115) + (d/135) = 5 kindly note.. its addition of two fractions... so I kindly take 5 common from both denominators... hence you will be left with d/23 + d/27 and that 5 will cross multiply to other side of equation.. resulting
d/23 + d/27 = 25
then kindly solve it ... 27d +23 d = 25*23*27
d will come down to 310.5
which i particularly took as total distance 310.5*2 = 621 km
hope it makes sense.
thanks

LaxAvenger wrote:
Celestial09 wrote:
Its D.
Here it goes:
Distance will be same both sides... hence total distance will D+D= 2D
Total time given+ 5hrs
Speed per side also given.. 115km/ph and 135 km/ph
Speed= Distanct/Time
D/s1 + D/s2= total time
(d/115) + (d/135) = 5
solving it D comes to 621 km
Hence each side is D/2 : 621/2 = 310.5 km
Time for first journey is 310.5/115 which is 162 mins
Thanks

Kudos please if my solution is correct!

Hello,

I have struggles coming from (D/115) + (D/135) = 5
to D = 621

could you explain the calculation steps ?
Math Expert
Joined: 02 Sep 2009
Posts: 44419
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

22 Feb 2015, 12:37
2
KUDOS
Expert's post
2
This post was
BOOKMARKED
Bunuel wrote:
While driving from A-ville to B-town, Harriet drove at a constant speed of 115 kilometers per hour. Upon arriving in B-town, Harriet immediately turned and drove back to A-ville at a constant speed of 135 kilometers per hour. If the entire trip took 5 hours, how many minutes did it take Harriet to drive from A-ville to B-town?

A. 138
B. 148
C. 150
D. 162
E. 168

Kudos for a correct solution.

MAGOOSH OFFICIAL SOLUTION
Attachment:

harriettakestrip_text.PNG [ 25.95 KiB | Viewed 5216 times ]

_________________
SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1838
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

11 Mar 2015, 21:07
1
This post was
BOOKMARKED

Let distance between A & B = d

Setting up the time equation

$$\frac{d}{115} + \frac{d}{135}= 5$$

$$d = \frac{23 * 27}{2}$$ (Need not have to solve)

Time required in minutes from A to B $$= \frac{23*27}{2*115} * 60 = 162$$
_________________

Kindly press "+1 Kudos" to appreciate

Intern
Joined: 16 Mar 2015
Posts: 9
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

23 Mar 2015, 08:48
Distance from A to B is the same as distance from B to A. Hence

115x=135y
x/y=135/115 => x/y=27/23
so x= 27/50 of the total time (50=27+23).
total time x+y=5h= 300minutes,

x= 300m*(27/50)= 162m

Intern
Joined: 30 Jun 2015
Posts: 1
Concentration: Finance, Entrepreneurship
GPA: 3.94
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

19 Jul 2015, 11:00
Hi everyone,

I don't see why we divide the distance 625 by 250 and not 115, while Harriet drives from A to B at 115mph...
Does not make sense to me.

But at the same time, dividing 625 by 115 gives us a time of 5+ hours, which is also impossible because the whole trip A --> B --> A takes 5 hours.
Can someone please give some insights?

Intern
Joined: 12 Jul 2015
Posts: 14
Concentration: Strategy, Finance
GPA: 3.62
WE: Project Management (Energy and Utilities)
While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

04 Sep 2016, 13:17
5hr = 300min.
If harriet spend equal hrs on each leg she will spend 150min on each. Since speed A-B is less than speed B-A and distance on each leg is the same, time spent on A-B is more than 150min, which mean we can eliminate ans. A, B and C.

Now let plug in ans. D or E and verify which one give same distance on each leg.

D. t= 162min
* leg A-B ---> d = 115.162/60 = 18630/60
* leg B-A ----> d = 135*138/60 = 18630/60

so the correct ans. is D
Manager
Joined: 17 Nov 2013
Posts: 167
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

13 Nov 2016, 10:35
Rates and Distance: Q: Find t on the way in?
When you are given the same distance on the way in and back. ex: d
and you are given the rates for back and forth. ex: 115 and 135
and you are given the total time. ex: 5

step1: organize the formulas like below. Use 5-t for the time on the way back = very important.

rt=d
115 (t) = d
135 (5-t) = d

step2: Make the two equations equal and solve for t

115(t) = 135 (5-t)
t= 27/10 hours

step3: check the convention of time that the question wants you to answer and convert if needed

In this question, you are asked for minutes, so you need to do one more thing before jumping into the answers

27/10 hours * 60minutes = 162 minutes
Intern
Joined: 22 Mar 2016
Posts: 2
Location: India
GPA: 3.8
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

13 Nov 2016, 10:49
2
KUDOS
Distance taken = speed*time
Let Harriet took x hrs to go from A to B and y hrs to come from B to A.
Distance=115*x=135*y
x+y=5 (total time=5 hrs.)
we need to find x.
y=5-x
Substituting in Distance equation.
115*x=135(5-x)
Solve to get x=2.7hrs
2.7*60=162mins.

Thanks. Please give KUDOS if correct.
Director
Joined: 07 Dec 2014
Posts: 929
While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

13 Nov 2016, 12:54
Bunuel wrote:
While driving from A-ville to B-town, Harriet drove at a constant speed of 115 kilometers per hour. Upon arriving in B-town, Harriet immediately turned and drove back to A-ville at a constant speed of 135 kilometers per hour. If the entire trip took 5 hours, how many minutes did it take Harriet to drive from A-ville to B-town?

A. 138
B. 148
C. 150
D. 162
E. 168

Kudos for a correct solution.

average speed for round trip≈125 kph
125*5=625 round trip miles
625/2=312.5 one way miles
312.5/115=2.72 hours
2.72*60=163.2 minutes
closest to 162
D
Retired Moderator
Joined: 05 Jul 2006
Posts: 1741
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

22 Nov 2016, 02:53
Bunuel wrote:
While driving from A-ville to B-town, Harriet drove at a constant speed of 115 kilometers per hour. Upon arriving in B-town, Harriet immediately turned and drove back to A-ville at a constant speed of 135 kilometers per hour. If the entire trip took 5 hours, how many minutes did it take Harriet to drive from A-ville to B-town?

A. 138
B. 148
C. 150
D. 162
E. 168

Kudos for a correct solution.

distance travelled is the same in each direction thus time is inversely proportional to speed , total time = 5 , let first leg time t and 2nd leg time = 5-t

115/135 = 5-t / t thus , t in hours = 5*27/50 , in minutes = 300*27/50 = 6*27 = 162..........D
Retired Moderator
Status: The best is yet to come.....
Joined: 10 Mar 2013
Posts: 527
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

02 Feb 2018, 23:32
I solved in following way;

Rate of driving from A-ville to B-town is 115 kmph
Rate of driving from B-town to A-ville is 135 kmph
Therefore, the ratio of rate is 115:135

Since the distance is same, the ratio of time would be reciprocal of ratio of rate.

So, ratio of time would be $$135:115=27:23; 27x:23x$$

Total time taken is 5 hours=300 minutes

$$27x+23x=50x$$

Given, $$50x=300$$
$$x=6$$

So, time taken to drive from A-ville to B-town would be $$27x=27*6=162$$
_________________

Hasan Mahmud

Senior Manager
Joined: 31 Jul 2017
Posts: 335
Location: Malaysia
WE: Consulting (Energy and Utilities)
Re: While driving from A-ville to B-town, Harriet drove at a constant spee [#permalink]

Show Tags

03 Feb 2018, 07:27
Bunuel wrote:
While driving from A-ville to B-town, Harriet drove at a constant speed of 115 kilometers per hour. Upon arriving in B-town, Harriet immediately turned and drove back to A-ville at a constant speed of 135 kilometers per hour. If the entire trip took 5 hours, how many minutes did it take Harriet to drive from A-ville to B-town?

A. 138
B. 148
C. 150
D. 162
E. 168

Kudos for a correct solution.

Let the time from A to B be t1 and time from B to A be t2.

$$t1 + t2 = 5$$

$$115*t1 = 135*t2$$ --> $$t2 = \frac{23}{27}t1$$
$$t1 = 2.7 Hours.$$
_________________

If my Post helps you in Gaining Knowledge, Help me with KUDOS.. !!

Re: While driving from A-ville to B-town, Harriet drove at a constant spee   [#permalink] 03 Feb 2018, 07:27
Display posts from previous: Sort by