BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

miles per gallon

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 117
Joined: Mon Oct 27, 2008 5:08 pm
Thanked: 1 times

miles per gallon

by [email protected] » Fri Nov 14, 2008 10:26 pm
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?

Ans)36
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 468
Joined: Sat Mar 03, 2007 10:17 pm
Thanked: 5 times

by moneyman » Fri Nov 14, 2008 11:41 pm
No.of miles per gallon = Total Distance / No.of gallons used

Total distance = 10+50=60

No.of gallons used = 2/5+5/4=33/20

No.of miles per gallon = 60/{33/20} =400/11 = Approx 36
Maxx
Top
Newbie | Next Rank: 10 Posts
Posts: 2
Joined: Sat Nov 15, 2008 2:49 am

by zelmac » Sat Nov 15, 2008 2:55 am
hello moneyman: just wanted to ask how you got 2/5 + 4/5 for the no. of gallons used. thanks. :)
Top
Legendary Member
Posts: 683
Joined: Tue Jul 22, 2008 1:58 pm
Location: Dubai
Thanked: 73 times
Followed by:2 members

by mals24 » Sat Nov 15, 2008 3:23 am
City

for every 25 miles the car uses 1 gallon of gasoline. (25mpg)
for 10 miles the car will use - (10*1)/25 = 2/5 (just cross multiply).

Highway

for every 40 miles the car uses 1 gallon of gasoline (40mpg)
for 50 miles the car will use - (50*1)/40 = 5/4

So combined gasoline consumed by car for 60 miles = 2/5+5/4

Hope it helps :)
Top
Newbie | Next Rank: 10 Posts
Posts: 2
Joined: Sat Nov 15, 2008 2:49 am

by zelmac » Sat Nov 15, 2008 7:13 am
to mals24: thank you very much for that! :)
Top
Post new topic Post Reply
• Page 1 of 1