Distance travelled

[sakshis]

Car X leaves Town A at 2 p.m. and drives toward Town B at a constant rate of m miles per hour. Fifteen minutes later, Car Y begins driving from Town B to Town A at a constant rate of n miles an hour. If both Car X and Car Y drive along the same route, will Car X be closer to Town A or Town B when it passes Car Y ?

(1) Car X arrives in Town B 90 minutes after leaving city A.

(2) Car Y arrives in Town A at the same time Car X arrived in Town B.


OA B

[Anurag@Gurome]

Car X leaves Town A at 2 p.m. and drives toward Town B at a constant rate of m miles per hour. Fifteen minutes later, Car Y begins driving from Town B to Town A at a constant rate of n miles an hour. If both Car X and Car Y drive along the same route, will Car X be closer to Town A or Town B when it passes Car Y ?

(1) Car X arrives in Town B 90 minutes after leaving city A.

(2) Car Y arrives in Town A at the same time Car X arrived in Town B.


OA B

(1) Car X arrives in Town B 90 minutes after leaving city A, but nothing has been said about car Y; NOT sufficient.

(2) Car Y arrives in Town A at the same time Car X arrived in Town B.
Since car Y starts 15 min after car X, so car X needs 15 min longer than car Y to cover the same distance. This implies speed of car X < Speed of car Y or m < n
No cars X and Y arrived at the same time, so they will take the same time to reach their destinations. This means that the distance covered by car Y after they meet (= nt) at a higher speed, will definitely be more than the distance covered by car X after they meet (= mt) at lower speed
OR as m < n, mt < nt; SUFFICIENT.

The correct answer is B.