If 68 % of people have an IQ between 85 and 115 what % have IQ > 130. Hint find the mean and standard deviation using the Empirical Rule of plus or minus one standard deviation from the mean for a 68 % spread,
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68% of the PEOPLE who take the test will score between 85 and 115. Statistically speaking 68.26% of the scores fall within plus or minus 1 SD of the mean. 95.44% of the scores fall within plus or minus 2 SD of the mean, and 99.74% of the scores fall within plus or minus 3 SD of the mean. Using this data, one could say that a PERSON with an IQ score of 122 would fall within plus or minus 2 SD of the mean. Two SD would be IQs from 70 to 130 since 2 SD would be 30 IQ points. Please note that if everybody scored the same on the test then the SD would be zero. And SD, for example, of 1.8 has scores closer to the mean (i.e., not as spread out or scattered) than an SD of 2.8. The greater the SD, the greater is the spread.
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