Last visit was: 23 Nov 2024, 13:39 It is currently 23 Nov 2024, 13:39

Close

GRE Prep 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
Your Progress

every week, we’ll send you an estimated GRE 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.

Close

Request Expert Reply

Confirm Cancel
GRE Prep Club Team Member
Joined: 20 Feb 2017
Posts: 2508
Own Kudos [?]: 3623 [3]
Given Kudos: 1053
GPA: 3.39
Send PM
Manager
Manager
Joined: 09 Nov 2018
Posts: 88
Own Kudos [?]: 95 [1]
Given Kudos: 0
Send PM
Manager
Manager
Joined: 11 Jan 2022
Posts: 71
Own Kudos [?]: 11 [0]
Given Kudos: 437
Send PM
Verbal Expert
Joined: 18 Apr 2015
Posts: 30010
Own Kudos [?]: 36366 [1]
Given Kudos: 25927
Send PM
Re: A certain car averages 25 miles per gallon of gasoline when driven in [#permalink]
1
Expert Reply
Chaithraln2499 wrote:
Is this a weighted average question?

GeminiHeat wrote:
A certain car averages 25 miles per gallon of gasoline when driven in the city and 40 miles per gallon when driven on the highway. According to these rates, which of the following is closest to the number of miles per gallon that the car averages when it is driven 10 miles in the city and then 50 miles on the highway?

(A) 28
(B) 30
(C) 33
(D) 36
(E) 38



Average miles per gallon is given by: Total distance traveled/Total gallons used.

Total distance traveled is given to us and is equal to 10+50 = 60 miles

Total gallons used can be determined by reverse working the formula listed above.

Number of gallons in the city = Total distance / Average = \(\frac{10}{25}\)

Number of gallons in the highway = Total distance / Average = \(\frac{50}{40}\)

Total number of gallons = Sum of the above two quantities.

So the average overall

\(\frac{60}{\frac{10}{25} + \frac{5}{4}} = \frac{60}{\frac{2}{5} + \frac{5}{4}} =
\frac{60}{\frac{33}{20}} = \frac{1200}{33} = \frac{400}{11}\)

If you solve this you get 36.3636. So the answer is 36.
Verbal Expert
Joined: 18 Apr 2015
Posts: 30010
Own Kudos [?]: 36366 [0]
Given Kudos: 25927
Send PM
Re: A certain car averages 25 miles per gallon of gasoline when driven in [#permalink]
Expert Reply
Prep Club for GRE Bot
Re: A certain car averages 25 miles per gallon of gasoline when driven in [#permalink]
Moderators:
GRE Instructor
84 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne