the test scores for a large statistics class have an unknown distribution with a mean of 70 and a standard deviation of 10(adsbygoogle = window.adsbygoogle || []).push({});

find k so that at most 10% of the scores are more than k standard deviations above the mean.

I'm a bit confused by the question it self.

does the question means :

1-1/k^2 = 0.1

k = 1.05

or

1-1/k^2 = 0.2

k = 1.12

or

1-1/k^2 = 0.8

k = square root 5 = 2.23

pls help, thanks in advance.

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# Chebyshevs theorem : find k so that at most 10%

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