It is currently 19 Sep 2017, 21:08

### 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

# At a speed of 50 miles per hour, a certain car uses 1 gallon

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 18 Sep 2009
Posts: 356

Kudos [?]: 572 [4], given: 2

At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

23 Sep 2010, 14:37
4
KUDOS
16
This post was
BOOKMARKED
00:00

Difficulty:

25% (medium)

Question Stats:

75% (01:04) correct 25% (01:20) wrong based on 1185 sessions

### HideShow timer Statistics

At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 12 gallon tank of gasoline and travels for 5 hours at 50 miles per hour, the amount of gasoline used would be what fraction of a full tank?

A. 3/25
B. 11/36
C. 7/12
D. 2/3
E. 25/36

I am getting 2/3 .Please explain what am i missing?
[Reveal] Spoiler: OA

Kudos [?]: 572 [4], given: 2

Math Expert
Joined: 02 Sep 2009
Posts: 41601

Kudos [?]: 124053 [12], given: 12070

At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

23 Sep 2010, 14:39
12
KUDOS
Expert's post
9
This post was
BOOKMARKED
At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 12 gallon tank of gasoline and travels for 5 hours at 50 miles per hour, the amount of gasoline used would be what fraction of a full tank?

A. 3/25
B. 11/36
C. 7/12
D. 2/3
E. 25/36

In 5 hours at 50 miles per hour car will travel 5*50=250 miles and thus will use 250/30=25/3 gallons of gasoline. Gasoline used/full tank equals to $$\frac{(\frac{25}{3})}{12} =\frac{25}{36}$$.

_________________

Kudos [?]: 124053 [12], given: 12070

Manager
Joined: 04 Aug 2010
Posts: 154

Kudos [?]: 30 [0], given: 15

### Show Tags

24 Sep 2010, 16:04
Gas used = (5 hours)*(50 miles/hour)*(1 gallon/30 miles) = 8+1/3 gallons
Portion used = (8+1/3) / 12 = 25/36

Ans E

Kudos [?]: 30 [0], given: 15

Intern
Joined: 10 Dec 2010
Posts: 1

Kudos [?]: [0], given: 0

### Show Tags

29 Dec 2010, 05:45

At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 12 gallon tank of gasoline and travels for 5 hours. the amount of gasoline used would be what fraction of full tank?

Thank you

KD

Kudos [?]: [0], given: 0

Manager
Joined: 07 Oct 2010
Posts: 175

Kudos [?]: 177 [0], given: 10

Re: GMAT Pre Q- Query [#permalink]

### Show Tags

29 Dec 2010, 07:53
In the given example SPEED is not mentioned with which the car traveled for 5 hrs with 12 gallons in the tank

Therefore, we have to assume that car traveled with the same speed

Now we can calculate distance traveled by the car in 5 hrs = D = S*t
= 50 * 5 = 250 miles

We know that car travels 30 miles in 1 gallon
Therefore gallons of fuel required for 250 miles = 25/3

Hence, fraction of fuel used = 25 /3*12 = 25 / 36

But according to me something is missed out in the question, because, mostly in GMAT answers are not awkward like this.

Kudos [?]: 177 [0], given: 10

SVP
Joined: 16 Nov 2010
Posts: 1605

Kudos [?]: 581 [1], given: 36

Location: United States (IN)
Concentration: Strategy, Technology

### Show Tags

26 Apr 2011, 06:44
1
KUDOS
Gasoline used = 250/30 = 25/3

Fraction used = 25/3/12 = 25/36

_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

GMAT Club Premium Membership - big benefits and savings

Kudos [?]: 581 [1], given: 36

Manager
Joined: 26 Jul 2010
Posts: 103

Kudos [?]: 30 [0], given: 6

Location: India
Concentration: Operations, General Management
Schools: IIMA (M)
GMAT 1: 640 Q48 V29
GMAT 2: 670 Q49 V31
WE: Supply Chain Management (Military & Defense)

### Show Tags

30 Apr 2011, 09:32
ans is e

in 5 hours car will travel 250 mile at the rate of 50 miles/hr

then gasoline consumed will be $$250/30= 25/3$$

=> fraction of gasoline used will be (25/3) / 12 === 25/36
_________________

lets start again

Kudos [?]: 30 [0], given: 6

Manager
Joined: 06 Jul 2011
Posts: 123

Kudos [?]: 105 [1], given: 240

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

30 May 2012, 11:50
1
KUDOS
Round off doesn't work.....250/30 is nearly 8.3 gallons..

Now 8.3/12 is not equal to 8/12(which most people who get wrong answer do) or 2/3 which is a trap and hence wrong answer...I fell in the trap,hence i know -:)

Kudos [?]: 105 [1], given: 240

Intern
Joined: 17 May 2013
Posts: 48

Kudos [?]: 13 [1], given: 8

GMAT Date: 10-23-2013
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

18 Aug 2013, 19:43
1
KUDOS
Speed - 50m/h
Consumption - 1gallon ever 30 miles
Given : 12 gallons of fuel at start
Expected travel on full Tank - 360m/h
Actual Travel : 5 * 50 = 250 m/h

Fraction would be : 250/360 = 25/36

Ans: E

Kudos [?]: 13 [1], given: 8

Intern
Joined: 30 May 2013
Posts: 4

Kudos [?]: [0], given: 33

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

18 Sep 2013, 00:38
2 / 3 is trap answer. you dont need to solve beyond 25 / 8 and get ~8. let 25 / 3 remain an then divide by 12 to get 25 / 36

TomB wrote:
At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 12 gallon tank of gasoline and travels for 5 hours at 50 miles per hour, the amount of gasoline used would be what fraction of a full tank?

A. 3/25
B. 11/36
C. 7/12
D. 2/3
E. 25/36

I am getting 2/3 .Please explain what am i missing?

Kudos [?]: [0], given: 33

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 17563

Kudos [?]: 270 [0], given: 0

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

11 Oct 2014, 15:14
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.
_________________

Kudos [?]: 270 [0], given: 0

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 17563

Kudos [?]: 270 [0], given: 0

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

01 Nov 2015, 22:00
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.
_________________

Kudos [?]: 270 [0], given: 0

BSchool Forum Moderator
Joined: 12 Aug 2015
Posts: 2222

Kudos [?]: 796 [0], given: 595

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

04 Dec 2016, 03:11
Great Question
Here is what i did in the one =>
At 50 miles/hour

Distance =250miles
so => Used gas => 1/30 *250 => 25/3

Let p be the required fraction.
25/3=p*12
p=25/36

Hence E

_________________

Give me a hell yeah ...!!!!!

Kudos [?]: 796 [0], given: 595

Intern
Joined: 07 May 2015
Posts: 23

Kudos [?]: 4 [0], given: 50

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

05 Dec 2016, 07:49
In 5 hrs the car will travel a distance of 250 miles.
1 gallon every 30 miles equates to 25/3 gallons for 250 miles
The amount of gasoline used would be (25/3)/12 = 25/36 gallon

2/3 = 0.6667
25/36 = 0.694
25/3 = 8.3
8.3/12 = 0.691
Hence E is better option than D

Kudos [?]: 4 [0], given: 50

Intern
Joined: 07 Mar 2016
Posts: 47

Kudos [?]: 13 [0], given: 18

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

11 Apr 2017, 13:34
Kind of an extremely long-winded way to answer this question, but it's how I best visualize it is: car travels 30 miles on 1 gallon. Trip total is 250 miles.

250-30=220..first gallon
220-30=210..second gallon
210-30=190..third gallon
190-30=160..fourth gallon
160-30=130..fifth gallon
130-30=100..sixth gallon
100-30=70..seventh gallon
70-30=40..eighth gallon
Left with 10 gallons which = 1/3 gallon

Total of 8.3 gallons over 12 gallon tank. The smallest that can reduce down to is 2/3 so answer choices A,B & C are all out. I then cross-multiplied the remaining two answer choices and got "E". Extremely step-oriented but for me it worked. Clocked-in at under 2 minutes to solve, though.

Kudos [?]: 13 [0], given: 18

Director
Joined: 17 Dec 2012
Posts: 601

Kudos [?]: 507 [0], given: 16

Location: India
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

30 May 2017, 17:26
TomB wrote:
At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 12 gallon tank of gasoline and travels for 5 hours at 50 miles per hour, the amount of gasoline used would be what fraction of a full tank?

A. 3/25
B. 11/36
C. 7/12
D. 2/3
E. 25/36

I am getting 2/3 .Please explain what am i missing?

1.In 5 hrs the car would have traveled 250 miles.
2. It would have used 250/30 gallons
3. The car started with full tank of 12 gallons
4. Gasoline used as a fraction of full tank is (250/30)/12=25/36
_________________

Srinivasan Vaidyaraman
Sravna
http://www.sravnatestprep.com/regularcourse.php

Free Online Coaching
Standardized Approaches

Kudos [?]: 507 [0], given: 16

Manager
Joined: 26 Mar 2017
Posts: 165

Kudos [?]: 7 [0], given: 1

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

08 Jun 2017, 09:23
arkle wrote:
Round off doesn't work.....250/30 is nearly 8.3 gallons..

Now 8.3/12 is not equal to 8/12(which most people who get wrong answer do) or 2/3 which is a trap and hence wrong answer...I fell in the trap,hence i know -:)

me too, so annoying
_________________

I hate long and complicated explanations!

Kudos [?]: 7 [0], given: 1

Manager
Joined: 20 Jan 2016
Posts: 129

Kudos [?]: 9 [0], given: 22

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

03 Aug 2017, 05:42
I fell for the trap answer as well. I rounded off 8.3/12 which is wrong.

I used the following method to solve this:

Distance= speed x time = 50x5=250 miles

Using ratios,
if 30 miles uses 1 gallon, how many gallons will be needed for 250 gallons?

Gallons needed= 250/30 x 1 = 25/3

Therefore, the answer will be (25/3)/12

Kudos [?]: 9 [0], given: 22

Intern
Joined: 30 Apr 2014
Posts: 5

Kudos [?]: 1 [0], given: 28

At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

06 Aug 2017, 14:36
It is important to see that all answer choices are in fraction form and hence do any calcs that way.

1 gallon = 30 miles travel

At a speed of 50 miles/hr for 5 hours , total distance travelled d
= $$\frac{50miles}{hr}$$*5hrs
= 250 miles

Total gasoline consumed = $$\frac{250}{30}$$ = $$\frac{25}{3}$$

Total gasoline consumed as part of the total gasoline available
= $$\frac{25}{3}$$*$$\frac{1}{12}$$
= $$\frac{25}{36}$$

Kudos [?]: 1 [0], given: 28

Intern
Joined: 24 Jan 2017
Posts: 4

Kudos [?]: [0], given: 6

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon [#permalink]

### Show Tags

08 Aug 2017, 03:20
GMAT40 wrote:
Speed - 50m/h
Consumption - 1gallon ever 30 miles
Given : 12 gallons of fuel at start
Expected travel on full Tank - 360m/h
Actual Travel : 5 * 50 = 250 m/h

Fraction would be : 250/360 = 25/36

Ans: E

Thanks a lot! The only option which clarified the last step of dividing by 12. This is the right way of determining the fraction of the done miles vs not done

Kudos [?]: [0], given: 6

Re: At a speed of 50 miles per hour, a certain car uses 1 gallon   [#permalink] 08 Aug 2017, 03:20

Go to page    1   2    Next  [ 21 posts ]

Similar topics Replies Last post
Similar
Topics:
A certain car averages 25 miles per gallon of gasoline when 7 13 Dec 2011, 00:09
6 A certain car can currently travel 17 miles per gallon of 5 06 Feb 2016, 10:23
46 A certain car averages 25 miles per gallon of gasoline when 17 29 Jul 2017, 04:30
30 A certain car averages 25 miles per gallon when driving in 22 25 Jun 2017, 12:42
2 Tara drove at an average speed of 50 miles per hour for the first 50 4 11 Sep 2017, 11:05
Display posts from previous: Sort by