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

 It is currently 18 Oct 2019, 19:09 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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.  At a speed of 50 miles per hour, a certain car uses 1 gallon of

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:

Hide Tags

Intern  Joined: 16 Apr 2010
Posts: 18
At a speed of 50 miles per hour, a certain car uses 1 gallon  [#permalink]

Show Tags

16 00:00

Difficulty:   25% (medium)

Question Stats: 77% (01:58) correct 23% (02:18) wrong based on 1175 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

Originally posted by kilukilam on 27 Jul 2010, 13:31.
Last edited by Bunuel on 09 Feb 2012, 14:18, edited 2 times in total.
Edited the question
Math Expert V
Joined: 02 Sep 2009
Posts: 58453
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon of  [#permalink]

Show Tags

17
12
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 $$\frac{(\frac{25}{3})}{12} =\frac{25}{36}$$.

_________________
General Discussion
Math Expert V
Joined: 02 Sep 2009
Posts: 58453
At a speed of 50 miles per hour, a certain car uses 1 gallon of  [#permalink]

Show Tags

9
10
Manager  Joined: 07 Oct 2010
Posts: 134
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon of  [#permalink]

Show Tags

2
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.
Manager  Joined: 25 May 2011
Posts: 97
Re: world problem  [#permalink]

Show Tags

1
1
My approach:

$$? Gal=5 hours*\frac{50 miles}{1 hour}*\frac{1 Gal}{30 miles}=\frac{25}{3}$$

We write the above equation while we are saying this: How many Gallon we need for 5 hours, while we know that in every 1 hour we go 50 miles, and we know that for every 30 miles we consume 1 Gallon.

and the fraction of used to total:$$\frac{\frac{25}{3}}{12}=\frac{25}{36}$$
Intern  Joined: 20 Feb 2012
Posts: 2
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon  [#permalink]

Show Tags

1
I did the problem differently. Is this a solid approach?

5 hours at 50 MPH, the car will travel 5*50=250 miles

Total capacity of the tank is 12 gallons. At 50 MPH, the car uses 30 miles per gallon.

30*12 = 360 gallons total

$$\frac{250 miles driven}{360 miles tank} = \frac{25}{36}$$
Math Expert V
Joined: 02 Sep 2009
Posts: 58453
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon  [#permalink]

Show Tags

bmwguy wrote:
I did the problem differently. Is this a solid approach?

5 hours at 50 MPH, the car will travel 5*50=250 miles

Total capacity of the tank is 12 gallons. At 50 MPH, the car uses 30 miles per gallon.

30*12 = 360 gallons total

$$\frac{250 miles driven}{360 miles tank} = \frac{25}{36}$$

The answer is correct but the reasoning is not.

We are told that the car uses 1 gallon of gasoline every 30 miles, so 12 gallons (full tank) of gasoline is enough to travel 12*30=360 miles. Since the car traveled only 250 miles, then it used 250/360=25/36 of full tank.

Hope it's clear.
_________________
Manager  Joined: 18 Dec 2014
Posts: 99
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon  [#permalink]

Show Tags

1
5 hours of driving @ 50 miles an hour; 250 total miles
1 liter per 30 miles; 250/30 = 8 1/3
8 1/3 x 3 = 25
12 x 3 = 36

25/36. E.
Target Test Prep Representative D
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8109
Location: United States (CA)
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon  [#permalink]

Show Tags

2
1
kilukilam 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

We are given that a certain car has a rate of 30 miles per gallon. We are next told that the car starts with a 12-gallon tank and travels for 5 hours at 50 miles per hour.

Since distance = rate x time, we know the car traveled 50 x 5 = 250 miles. We can use the car’s rate and distance traveled to determine how many gallons were used.

Gallons used = distance/rate

Gallons used = 250/30 = 25/3

Finally, we need to determine the amount of gasoline used as a fraction of a full 12-gallon tank.

(25/3)/12 = (25/3) x (1/12) = 25/36

_________________

Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com

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.

Director  S
Joined: 17 Dec 2012
Posts: 626
Location: India
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon of  [#permalink]

Show Tags

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 Test Prep
http://www.sravnatestprep.com

Holistic and Systematic Approach
GMAT Club Legend  V
Joined: 12 Sep 2015
Posts: 4009
Re: At a speed of 50 miles per hour, a certain car uses 1 gallon of  [#permalink]

Show Tags

Top Contributor
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

At a speed of 50 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles.
Time = distance/speed
So, time to travel 30 miles = 30/50 = 3/5 hours.
This means that the car uses 1 gallon for every 3/5 hours.

Let x = the number of gallons of gas used during the 5 hour trip.

We get the following equivalent ratios: 1/(3/5) = x/ 5
Cross multiply to get: 5 = (3/5)x
Multiply both sides by 5/3 to get: 25/3 = x
So, the car uses 25/3 gallons of gas

The amount of gasoline used would be what fraction of a full tank?
We get (25/3)/12, which equals 25/36

Cheers,
Brent
_________________
Non-Human User Joined: 09 Sep 2013
Posts: 13262
Re: At a speed of 50 mp/h, a certain car uses 1 gallon of  [#permalink]

Show Tags

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: At a speed of 50 mp/h, a certain car uses 1 gallon of   [#permalink] 23 Jul 2019, 06:49
Display posts from previous: Sort by

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

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne  