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Nolse Levels in Mospitals in a hospital study, it was found that the standard deviation of the sound levels from 30 areas designeted as "cawsity doors" Was 7.8 dBA and the standard deviation of 22 areas designated as operating theaters was 6.1 ABA. At α=0.05, can you substantiate the daim that there is a diference in the standard devations? Use σ 1 ​ for the standard devilion of the sound levels frem areas designated as "casualty doors." Part: 0/5 Pist 1 ot 5 (a) Stase the hypetyeses and identify the daim.

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Final answer:

The hypotheses for testing the difference in standard deviations of sound levels at casualty doors and operating theaters are the null hypothesis (no difference) and the alternative hypothesis (a difference exists). The claim being tested is that there is a significant difference, and an F-test at a 0.05 significance level will be used to substantiate this claim.

Step-by-step explanation:

Hypothesis Testing for Two Variances

To address whether there is a difference in the standard deviations of sound levels in different areas of a hospital, we need to conduct a hypothesis test for two variances. First, we formulate the hypotheses:

Null hypothesis (H0): The two population variances are equal, σ12 = σ22, meaning the standard deviation of sound levels at casualty doors is the same as in operating theaters.

Alternative hypothesis (HA): The two population variances are not equal, σ12 ≠ σ22, which means there is a difference in the standard deviations of sound levels.

In this scenario, the claim is the alternative hypothesis which suggests that there is a statistically significant difference in the standard deviations (or variances) between the two designated hospital areas. At an α = 0.05 significance level, we will test this claim using an appropriate statistical test, such as an F-test for variances.

If the F-test statistic calculated from the sample standard deviations falls beyond the critical value from the F-distribution table, we will reject the null hypothesis in favor of the alternative hypothesis.

Remember that improper interpretation of statistical tests can lead to incorrect conclusions, so careful consideration of the results and their context within the study is essential.

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