time speed dist

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time speed dist

by mitaliisrani » Mon Aug 23, 2010 9:58 am
Boston is 4hr ahead of Frankfurt 2 hr behind India. X leaves Frankfurt at 6pm on Friday and reaches Boston the next day. After waiting there for 2hrs, he leaves exactly at noon and reaches India at 1 am. On his return journey he takes the same route as before, but halts at Boston for 1 hr less than previous halt there. He then proceeds to Frankfurt.

If his journey from F to I, including stoppage, is covered at an average speed of 180mph, What is the distance betwwen Frankfurt and India?
A)3600miles
B) 4500 miles
C) 5580 miles
D) 4150miles
E) Data insufficient

is it C ?

If X had started the return journey at 2.55am on the same day that he reached there, after how much time would he reach Frankfurt?
A) 24hr
B) 25hrs
C)26hrs
D) 23hrs
E) Data insufficient
din understand.. 2.55 pm ?

What is X's average speed for the entire journey
A) 176mph
B) 180mph
C) 165mph
D) 166mph
E) Data insufficient

OA is B,A,E

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by 4GMAT_Mumbai » Mon Aug 23, 2010 11:19 am
Hi,

X reaches Boston at 10 AM. At the same moment, time in Frankfurt is 6 AM. Hence, the journey time was 12 hours.

X reaches India at 1 AM. At the same moment, time in Boston is 11 PM. Hence, the journey time was 11 hours.

Waiting time = 2 hours.

So, total time = 12 + 2 + 11 = 25 hours.

Avg speed = 180 mph

Distance = 180 times 25 = 4,500 miles.

Hope this helps. Thanks.
Naveenan Ramachandran
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai

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by 4GMAT_Mumbai » Mon Aug 23, 2010 11:21 am
Q2 - the only difference in the return journey is that she waits 1 hour lesser in transit.

Previous time = 25 hours.

Now, her travel time = 24 hours. And hence, 2:55 AM (same time, next day)
Naveenan Ramachandran
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai