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Are Variance questions tested on the GMAT ?
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Black Knight
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I need some advice from experts ? Is Variance a concept which maybe tested on the GMAT ?
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Geva@EconomistGMAT
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Yes, but very rarely - I think I've seen ONE GMATPREP question which mentioned Variance.Black Knight wrote:I need some advice from experts ? Is Variance a concept which maybe tested on the GMAT ?
You won't need to calculate the statistic. All you really need to know is what Variance MEASURES - a measure of the dispersal of the terms of a set around its axis (same as standard deviation).
A big Variance means that the terms are spread out around the average of the set.
A small Variance means that the terms are clustered around the average of the set.
a Variance of Zero means that there is NO dispersal - that all the terms are equal to each other, and equal to the average. The sets (5,5,5,5) or (100, 100, 100, 100, 100, 100) both have a variance of zero.
The above also applies to standard deviation.
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Frankenstein
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Hi,Black Knight wrote:I need some advice from experts ? Is Variance a concept which maybe tested on the GMAT ?
If you already know about standard deviation, you just need to know only one more thing.
Variance is nothing but square of standard deviation.
Cheers!
Things are not what they appear to be... nor are they otherwise
Things are not what they appear to be... nor are they otherwise
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Black Knight
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Ian Stewart
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I have seen one, and only one, official question which mentions variance (and I've probably seen somewhere between 5000 and 10,000 official questions by now). That question is in the diagnostic test at the start of OG12. For that question, you only need to know that you can find the standard deviation if you know the variance (technically, standard deviation is the square root of the variance, but you don't even need to know that much). That's it.
It is *extremely* unlikely you will see 'variance' mentioned anywhere on your GMAT.
It is *extremely* unlikely you will see 'variance' mentioned anywhere on your GMAT.
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com
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