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Error probabilities and power


Asha owns a car wash and is trying to decide whether or not to purchase a vending machine so customers can buy coffee while they wait. She'll get the machine if she's convinced that more than 30% of her customers would buy coffee. She plans on taking a random sample of n customers and asking them whether or not they would buy coffee from the machine, and she'll then do a significance test using α=0.05 to see if the sample proportion who say "yes" is significantly greater than 30%.
Which situation below would result in the highest power for her test?
Choose 1 answer: