Three neighborhood children, individually, can mow Mr. Phelp

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Three neighborhood children, individually, can mow Mr. Phelps's lawn in 1.5, 2, and 3 hours, respectively. What is the fastest the job can be completed by two of the children working together at their respective rates?

a) 6/7 hours
b) 3/2 hours
c) 7/4 hours
d) 7/2 hours
e) 5 hours

Please assist with above problem.

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by [email protected] » Sun Oct 16, 2016 9:44 am
Hi alanforde800Maximus,

What is the source of this question? I ask because you can answer it with 10 seconds of logical thinking and no actual work - and you're not likely to see questions designed in that way on the GMAT.

Since the individual times it takes to mow the lawn are 1.5 hours, 2 hours and 3 hours, the fastest child can mow the lawn by himself in 1.5 hours. If he has help, then it would take LESS time than that...

Final Answer: A

GMAT assassins aren't born, they're made,
Rich
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by alanforde800Maximus » Mon Oct 17, 2016 5:45 am
Hello Rich,

The source is Veritas Prep Material. I have attached the pic of question from the manual.
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