Name Unit 10 Test - Inference for Means Part A: Open Response 1. Use the following information: The Wechsler Adult Intelligence Scale (WAIS) is a common "IQ test" for adults. The distribution of WAIS scores for persons over 16 years of age is approximately normal with mean 100 and standard deviation 15. x a. What is the probability that a randomly chosen individual has a WAIS score of 105 or higher? Show your work. mean - 100 / 2 = X-M 80:8-15 0/5n n=60 = 100-105 1515 n=60 Theun- Ī¼ = 100 SD = 0 = 15 Period b. What are the mean and standard deviation of the sampling distribution of the average WAIS score x a SRS of 60 people? S 15 = 15 ć 60 7.745 -1.936 % confidence interval when n = 25 E ā¢ mean - 100 SD - 1.936 c. What is the probability that the average WAIS score of an SRS of 60 people is 105 or higher? Show your work or provide "calculator talk". Find the critical t* value for each of the following confidence intervals: (Providing calculator talk will be howing work) 92% confidence interval with 12 de
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Step 1: To find the probability that a randomly chosen individual has a WAIS score of 105 or higher, we need to standardize the score using the z-score formula: z = (x - Ī¼) / Ļ, where x is the score, Ī¼ is the mean, and Ļ is the standard deviation. Show moreā¦
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