Respuesta :
Answer:
C. The critical z-score is indeed 1.95, the one-sided significance level is 9%, and the rejection region includes both tails.
Step by step Explanation:
Step 1: Understanding the significance level The significance level represents the probability of rejecting the null hypothesis when it is actually true. In this case, the significance level is 18%.
Step 2: Identifying the critical z-score The critical z-score is the value on the standard normal distribution that corresponds to the specified significance level. In this case, the critical z-score is 1.95.
Step 3: Determining the rejection region Since it is a two-sided test, the rejection region includes both tails of the distribution. This means that any z-score beyond the critical z-score in either direction would lead to rejecting the null hypothesis. So, to summarize: - The critical z-score is 1.95. - The one-sided significance level is 9%. - The rejection region includes both tails.
Final answer:
The critical z-score for a two-sided test at an 18% significance level is 1.95. Critical z-score: -1.95; One-sided significance level: 9%; Rejection region: Both tails (option D is the correct answer).
Explanation:
For a two-sided test at an 18% significance level, we need to find the critical z-score that corresponds to the central region containing 1 - 18% = 82% of the data. The critical z-score for this is 1.95. For a two-sided test, we need to consider both tails, so we divide the significance level by 2. Thus, the one-sided significance level is 9% (18% / 2 = 9%). The rejection region includes both tails, so the critical z-score is -1.95 on the left tail and 1.95 on the right tail.
Hence, the correct answer is D. Critical z-score: -1.95; One-sided significance level: 9%; Rejection region: Both tails. This option accurately represents the critical z-scores, the one-sided significance level, and the rejection region for a two-sided test at an 18% significance level.
