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

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IQ scores follow a normal distribution with a mean of 100 and a standard deviation of 15. The discussion focuses on determining the proportion of individuals with IQs above 130, which is two standard deviations above the mean. It is established that approximately 95% of the population falls within two standard deviations of the mean, leaving about 5% in the tails. Since the question specifically asks for the proportion above 130, the answer is 2.5%. Understanding the normal distribution is crucial for interpreting these statistics accurately.
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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.
 
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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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