-14.1 ....standard deviation of 15......

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The discussion centers on the normal distribution of IQ scores, which have a mean of 100 and a standard deviation of 15. It is established that an IQ of 130 is two standard deviations above the mean. Consequently, approximately 95% of the population falls within two standard deviations, leaving about 5% of individuals with IQs above 130. The correct answer to the posed question is therefore option c, 5%.

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karush
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Given IQ scores are approximately normally distributed with a mean of 100 and standard deviation of 15,
the proportion of people with IQs above 130 is:
$ a.\ 95\% \quad b.\ 68\% \quad c.\ 5\% \quad d.\ 2.5\% \quad e.\ 12\%$

ok its been some moons since I looked at a standard deviation graph
so my choice would be by dice.
 
Last edited:
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It's not a "standard deviation graph", it's a normal distribution graph.

130 is two standard deviations above the mean. How much of the data will be within two standard deviations from the mean? So how much for each tail?
 
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Last edited:

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