Confusing PS

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Confusing PS

by GmatKiss » Wed Aug 24, 2011 6:01 am
A cyclist travels the length of a bike path that is 225 miles long, rounded to the nearest
mile. If the trip took him 5 hours, rounded to the nearest hour, then his average speed
must be between:

(A) 38 and 50 miles per hour
(C) 40 and 51 miles per hour
(E) 41 and 51 miles per hour
(B) 40 and 50 miles per hour
(D) 41 and 50 miles per hour

Please help with explanation!

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by arashyazdiha » Wed Aug 24, 2011 6:24 am
Hi,
Distance must be between 224.5 and 225.5 non-inclusive.
and the time must be between 4.5 and 5.5 non-inclusive.
so the maximum speed is 225.5/4.5 which is 50.111111111
and the minimum speed is 224.5/5.5 which is 40.81818181
so it is between 40 and 51.

Bests
Arash

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by kmittal82 » Wed Aug 24, 2011 6:26 am
>225 miles long, rounded to the nearest mile
Means the distance was between 224.5 and 225.5

>If the trip took him 5 hours, rounded to the nearest hour
Means the time taken was between 4.5 hrs and 5.5 hrs

His "fastest" speed in this case would be 225.5/4.5 which is 50.1
His "Slowest" speed would be 224.5/5.5 which is appx 40.8

So his speed must be between 40 and 51 miles per hour

OA?

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by GmatKiss » Thu Aug 25, 2011 5:38 am
OA: 40 and 51