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in the population, the average IQ is 100. A team of researchers wants to test a...

in the population, the average IQ is 100. A team of researchers wants to test a new coaching method to see if it has any effect at all on students. a sample of 30 participants who were coached have a mean IQ score of 140 with a standard deviation of 20. did coaching affected intelligence?
define null hypothesis, state the alpha level, state decision rule, calculate the test statistic, state result, state conclusion

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