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AP®︎/College Statistics

Course: AP®︎/College Statistics > Unit 10

Lesson 7: Potential errors when performing tests

Error probabilities and power

AP.STATS: UNC‑5 (EU), UNC‑5.B (LO), UNC‑5.B.1 (EK), UNC‑5.C (LO), UNC‑5.C.1 (EK)

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, percent 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 alpha, equals, 0, point, 05 to see if the sample proportion who say "yes" is significantly greater than 30, percent.

Which situation below would result in the highest power for her test?

(Choice A)
She uses a sample size of n, equals, 100, and 32, percent of all customers would actually buy coffee.
(Choice B)
She uses a sample size of n, equals, 200, and 32, percent of all customers would actually buy coffee.
(Choice C)
She uses a sample size of n, equals, 50, and 50, percent of all customers would actually buy coffee.
(Choice D)
She uses a sample size of n, equals, 200, and 50, percent of all customers would actually buy coffee.

Stuck?

AP®︎/College Statistics

Course: AP®︎/College Statistics > Unit 10

Problem