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by sk818020 » Tue May 18, 2010 8:26 am
(1) is insufficient because it says that when they passed P has average speed 70mph. This only tells us what his average speed was at that particular moment. It doesn't say what the speed the rest of the trip was. Thus, we cannot say exactly where they were at.

(2) Tell us that at 2 hours Q would have traveled 2(55)=110 miles. If Q traveled 110 miles and at that point P is at the same spot on the other rail, P must have traved 250-110=140 miles. Therefore, P is closer to its destination. (2) is sufficient.

IMO the answer is B.

What is the OA?

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by bharatishiv » Tue May 18, 2010 7:17 pm
sk818020 wrote:(1) is insufficient because it says that when they passed P has average speed 70mph. This only tells us what his average speed was at that particular moment. It doesn't say what the speed the rest of the trip was. Thus, we cannot say exactly where they were at.

(2) Tell us that at 2 hours Q would have traveled 2(55)=110 miles. If Q traveled 110 miles and at that point P is at the same spot on the other rail, P must have traved 250-110=140 miles. Therefore, P is closer to its destination. (2) is sufficient.

IMO the answer is B.

What is the OA?

I agree with Statement 2....
But, what I am trying to understand about Stmt 1 is that it says "At the time when 2 trains passed, train P had averaged speed of 70mph"....does it mean that train P had an average speed of 70mph after the 2 trains passed or was the speed 70mph until they crossed each other?

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by sk818020 » Tue May 18, 2010 7:23 pm
I agree with Statement 2....
But, what I am trying to understand about Stmt 1 is that it says "At the time when 2 trains passed, train P had averaged speed of 70mph"....does it mean that train P had an average speed of 70mph after the 2 trains passed or was the speed 70mph until they crossed each other?
I'll have to retract my previous statement. Sorry I missed the key word had. The answer is D.

(1) Says that when P and Q passed each other P had averaged 70 miles per hour. If it has traveled for 2 hours at 70 miles per hour. P has traveled 140 miles (70*2). Which means that Q had traveled 250-140=110 miles. So, P had traveled further. (1) is sufficient.

Thus D should be the answer, either is sufficient.[/quote]

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by DeepthiRajan » Tue May 18, 2010 9:03 pm
The answer is A.

Please refer to an earlier post:
https://www.beatthegmat.com/stations-x-a ... 52880.html