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georgepa
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WP (3) - 5th ed. Ch 2 #8, Mary and Nancy can each perform

by georgepa Mon Jun 24, 2013 2:27 am

Mary and Nancy can each perform a certain task in m and n hours, respectively. Is m<n?

(1) 2t > m
(2) 2t < n

I understand the main solution, but I'm having difficulty understanding the alternate solution.

Consider (1) alone

2t > m => t > m/2.

The strategy guide explains: If both Mary and Nancy worked at Mary's rate, then together, they would complete the task in m/2 hours. Since the actual time is longer, Nancy must work more slowly than Mary, and thus n < m

I see that given t > m/2, m is different from n. I put in numbers and I see the relationship is true - but I'm still not able to clearly see why this is the case.

Can someone explain it differently?
RonPurewal
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Re: WP (3) - 5th ed. Ch 2 #8, Mary and Nancy can each perform

by RonPurewal Fri Jun 28, 2013 5:39 am

hi,
it appears you haven't posted the entire question (and/or the entire context of the question), since the quantity "t" is not defined or addressed in any way whatsoever in the question.
could you please write out the entire question prompt? or, if "t" is already understood to mean something, could you please say what that is?

thanks.