OG 11 PS 90

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OG 11 PS 90

by cholloway » Thu Jul 23, 2009 5:28 pm
At the rate of m meters per s seconds, how many meters does a cyclist travel in x minutes?

A) m/sx
B) mx/s
C) 60m/sx
D) 60ms/x
E) 60mx/s

Answer is E

Part of the answer is a little fuzzy, I want to see how you solve.

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by shibal » Thu Jul 23, 2009 6:25 pm
plug in #

10m/s in one min ===> he'd travel 600 meter right?

the only equation that gives us that answer is E

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by cholloway » Thu Jul 23, 2009 7:27 pm
Thanks for the explanation.. I just realized the S on the bottom is a relative term. I was interpretting S incorrectly as one second, where actually it can be any amount of seconds.. 1 Min != 60s, 1Min= s 2 min=s and so on.

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by mbadrew » Thu Jul 23, 2009 8:19 pm
The easiest way to solve this problem is to break it down in pieces

meters per second = m/s

How many meters per second? So we use X as the unknown variable, so you end up with mx/s.

Now the last part of the question requires an answer in minutes, so we convert the unit seconds into minutes, which gives the answer 60mx/s.

Hope this helps.

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by cholloway » Fri Jul 24, 2009 9:31 am
The thing that throws me off is having the time unit on the bottom. I thought when you multiply the rate by the time the units of time should cancel out.