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# Hypothesis Testing: Testing for proportions

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Joe thinks that no more than 20% of students in his Statistics class will get an A in the final examination. To prove his claim, he takes a random sample of 35 students and finds to his surprise that 30% of students got an A. At a 0.01 percent level of significance can we reject Joe's claim?

https://brainmass.com/statistics/hypothesis-testing/hypothesis-testing-testing-proportions-15110

#### Solution Preview

I am assuming the level of significance is 0.01 and not 0.01%. Because if it is 0.01% then it would mean that the acceptance region is 99.99 %. Which would mean that rejection region is very small

Null Hypothesis:Ho: p=0.2
Proportion of students getting an A is 20%
Alternative Hypothesis:H1: > 0.2
Proportion of students getting an A is greater than 20%

p= 20.00% =Hypothesized proportion of students getting an A
q=1-p= 80.00% ...

#### Solution Summary

The solution tests the hypothesis that no more than 20% of students in Statistics class will get an A in the final examination

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