robypeter wrote:

I am trying to use relative speed to solve this. So my thoughts are that Linda after 1 hour is 2 miles away, at which point Tom starts jogging. If I imagine Linda stationary, Tom's relative speed would be 8 miles per hour, and I would have to find the time it would take him to run 1 mile and 4 miles, but that doesn't work. Can somone explain to me why relative speed does not work in this case. Thank you!

Hi,

The problem is that you are just working on initial 2 mile or 1 hour....

1 mile or 4 milesBut the half distance and twice the distance involves travelled distance after initial 1 hour

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1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372

2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

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