M7MBA wrote:If two trains ,travelling at a speed of 72mph and 48 mph respectively, are approaching each other from opposite direction; what is the distance between them 1 minute before the collision ?
A)2 miles
B)3 miles
C)4 miles
D)5 miles
E)none of the above.
Since the trains travel toward each other, they WORK TOGETHER to cover the distance between them.
When elements work together, ADD THEIR RATES.
Combined rate for the two trains = 72+48 = 120 miles per hour = 2 miles per minute.
Let the TOTAL travel time for the two trains = 1 minute.
Let the faster train start at Point A and the slower train start at Point B.
The question stem becomes:
If it takes 1 minute for the two trains to meet, what is the distance between Point A and Point B?
Since the two trains travel at a combined rate of 2 miles per minute for a total time of 1 minute, the distance between Point A and Point B = rt = 2*1 = 2 miles.
The correct answer is
A.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at
[email protected].
Student Review #1
Student Review #2
Student Review #3
