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 drives 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
I got C...can someone explain how to get the right answer
Could use help on this one
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That's a nice one question, thanks for posting it.
1)
We are ok it is useless by itself.
2) Car Y arrives in Town A at the same time Car X arrived in Town B
We have two cars. We have two different speeds. We know X starts 15' before Y, and they arrive at their destination at the same time and drove the same number of kilometers; we can infer that the speed of X is lower than the speed of Y.
You have the city A, the city B and the middle of the distance is M.
A-------------M----------------B
Imagine X see Y between A and M, there is a big problem because X is slower than Y and X has to drive more kilometers than Y ! X will never arrive at B at the same time Y does at A.
That is the same if they see each other at M, it's over for X, it is slower than Y.
So, X will see Y between M and B, closer to B than to A.
So your answer is B
1)
We are ok it is useless by itself.
2) Car Y arrives in Town A at the same time Car X arrived in Town B
We have two cars. We have two different speeds. We know X starts 15' before Y, and they arrive at their destination at the same time and drove the same number of kilometers; we can infer that the speed of X is lower than the speed of Y.
You have the city A, the city B and the middle of the distance is M.
A-------------M----------------B
Imagine X see Y between A and M, there is a big problem because X is slower than Y and X has to drive more kilometers than Y ! X will never arrive at B at the same time Y does at A.
That is the same if they see each other at M, it's over for X, it is slower than Y.
So, X will see Y between M and B, closer to B than to A.
So your answer is B
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