While on straight, parallel tracks, train A and train B are traveling at different constant rates. If train A is currently 2 miles behind train B, how many minutes from now will train A be 4 miles behind train B?
(1) Three minutes ago, train A was 1 mile behind train B.
(2) Train A is traveling at 80 miles per hour, and train B is traveling at 100 miles per hour.
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train A and B
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j_shreyans
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Statement 1:j_shreyans wrote:While on straight, parallel tracks, train A and train B are traveling at different constant rates. If train A is currently 2 miles behind train B, how many minutes from now will train A be 4 miles behind train B?
(1) Three minutes ago, train A was 1 mile behind train B.
(2) Train A is traveling at 80 miles per hour, and train B is traveling at 100 miles per hour.
3 minutes ago, train B was 1 MILE AHEAD of train A.
Now -- 3 minutes LATER -- train B is 2 MILES AHEAD of train A.
Implication:
Every 3 minutes, train B pulls ahead of train A by 1 more mile.
Thus:
6 minutes from now, train B will pull ahead of train A by 2 more miles, with the result that train A will be 4 miles behind train B.
SUFFICIENT.
Statement 2:
Since the speed of each train is known, we can determine how long it will take train A to be 4 miles behind train B.
SUFFICIENT.
The correct answer is D.
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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].
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