People walking

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People walking

by muzali » Wed Nov 26, 2008 4:15 pm
Two people walked the same distance, one person's speed is between 25 and 45,and if he used 4 hours, the speed of another people is between 45 and 60,and if he used 2 hours, how long is the distance?
A.116 B.118 C.124 D.136 E.140
Source: — Problem Solving |

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by muzali » Wed Nov 26, 2008 5:10 pm
The linked post above gives no satisfactory way of solving it. Infact the proposed soultion does 4*45 = 130!

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Re: People walking

by Stuart@KaplanGMAT » Wed Nov 26, 2008 5:30 pm
muzali wrote:Two people walked the same distance, one person's speed is between 25 and 45,and if he used 4 hours, the speed of another people is between 45 and 60,and if he used 2 hours, how long is the distance?
A.116 B.118 C.124 D.136 E.140
The question as written has an infinite number of answers.

All we know is that the second person travelled at twice the speed of the first. Given the ranges, their rates could be:

27/54
28/56
29/58

and on and on (the rates don't have to be integers, hence the infinite possibilities). For each set of rates, we get a different distance.

Even among the choices, (A) and (B) are both possible (for (A) the rates would be 29/58, for (B) the rates would be 29.5/59).

So, the question fails on grammar AND math!

Please post the source of your questions, I'd never use this source again.
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