GRE Math Tricks: Method for approaching questions with variables in the answers

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[sebtamgeospa]

Could you please elaborate your answer. How and why did you choose 3 yards, 30 minutes, and 2 hours? Why did you come up with these specific numbers? Thanks!

[MagooshGRE]

@sebtamgeospa Because we're testing the different answers, we can choose whatever numbers we like for each variable. If we can choose whatever numbers we like, why not choose easy numbers that make the math simple and give easy answers? Here, we chose 3 yards, 30 minutes, and 2 hours because they all divide easily from 60 (from the answer choices). If we chose 8 yards instead for example, we would have to divide 60 by 8, which is not nearly as easy as dividing 60 by 3. Hope that helps!

[ColdHeartedMan86]

@Farawla of couse...

Kevin rides his bike at a c. speed of x yeards per min -> speed: x/m

1 hour are 60 mins -> 60x/m

for h hours -> h60x/m

or write it a bit more nice:

60h(x/m) -> 60h(yeards/minute)

i would not plugin numbers in the other equations, only one could be right and if this hold - all other don't. (Besides the evidence of the other is required.)

[Farawla]

is there a quicker way to executing this question? This takes too much time!!!

[WellConditionedChimp]

this is a time consuming method. the factor label method, where you start from the thing being asked for, and work your way forward from there, works faster, I think