A researcher has determined that she requires a minimum of n responses to a survey for the results to be valid. If p% of the surveyed individuals fail to respond to the survey, how many individuals, in terms of n and p, must the researcher survey to produce twice the minimum required number of responses?
A) 200n/100-p
B) 2n/100-p
C) 200n/p
D) 2n(100+p)/100
E) 2n+2np/100
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A researcher has determined that she requires a minimum of n
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Hi rsarashi,
This question was discussed here:
https://www.beatthegmat.com/a-researcher ... 85176.html
GMAT assassins aren't born, they're made,
Rich
This question was discussed here:
https://www.beatthegmat.com/a-researcher ... 85176.html
GMAT assassins aren't born, they're made,
Rich
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Matt@VeritasPrep
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If we send out x surveys, we know that (1 - p/100), or (100 - p)/100 people will respond.
We want that number to be at least 2n, so
x * (100 - p)/100 = 2n
x = 2n * 100 / (100 - p)
and our answer is A.
We want that number to be at least 2n, so
x * (100 - p)/100 = 2n
x = 2n * 100 / (100 - p)
and our answer is A.
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Matt@VeritasPrep
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We could also always pick our own numbers: this is a great, mostly foolproof way to get the answer on the test when you either can't set up the algebra or fear that you've written the wrong equation.
Suppose n = 50 and p = 20. Then we're going to need 125 surveys.
Plugging n = 50 and p = 20 into the answers, we want the answer that gives 125. A works, so we're set!
Suppose n = 50 and p = 20. Then we're going to need 125 surveys.
Plugging n = 50 and p = 20 into the answers, we want the answer that gives 125. A works, so we're set!
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Scott@TargetTestPrep
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Let x = total number of people she surveys. Therefore, we have:rsarashi wrote: ↑Sat May 20, 2017 10:46 pmA researcher has determined that she requires a minimum of n responses to a survey for the results to be valid. If p% of the surveyed individuals fail to respond to the survey, how many individuals, in terms of n and p, must the researcher survey to produce twice the minimum required number of responses?
A) 200n/100-p
B) 2n/100-p
C) 200n/p
D) 2n(100+p)/100
E) 2n+2np/100
OAA
x(1 - p/100) = 2n
x(100 - p)/100 = 2n
x = 2n * 100/(100 - p)
x = 200n/(100 - p)
Answer: A
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