Adam and Beth each drive from Smallville to Crown City by different routes. Adam drove at an average speed of 40 miles per hour and completed the trip in 30 minutes. Beth's route was 5 miles longer and it took her 20 minutes more than Adam to complete the trip. How many miles per hour was Beth's average speed on this trip?
A. 24
B. 30
C. 48
D. 54
E. 75
Could someone shed light on this problem?
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
GMAT Prep: Distance and Speed problem
This topic has expert replies
-
rookieingmat
- Junior | Next Rank: 30 Posts
- Posts: 11
- Joined: Mon Jun 23, 2008 1:42 pm
-
gmataspirant
- Senior | Next Rank: 100 Posts
- Posts: 52
- Joined: Mon Jan 14, 2008 7:46 pm
- Thanked: 3 times
My approach..
Let's find the distance travelled by Adam. Travel time is 30 minutes @ a speed of 40, so d=ts i.e d=30/60 * 40 = 20.
Beth has travelled 5 miles longer so Beth's distance is Adam's Distance + 5 => 20 + 5 ==>25
Beth's speed is s=d/t ==> 25 /50/60 ==> 25 * 60 /50 ==> 30 MPH.
Answer is B, What is OA ?
Let's find the distance travelled by Adam. Travel time is 30 minutes @ a speed of 40, so d=ts i.e d=30/60 * 40 = 20.
Beth has travelled 5 miles longer so Beth's distance is Adam's Distance + 5 => 20 + 5 ==>25
Beth's speed is s=d/t ==> 25 /50/60 ==> 25 * 60 /50 ==> 30 MPH.
Answer is B, What is OA ?
Never GiveUp For Any Reason
-
rookieingmat
- Junior | Next Rank: 30 Posts
- Posts: 11
- Joined: Mon Jun 23, 2008 1:42 pm
