One:

In a study, researchers wanted to measure the effect of alcohol on the hippocampal region, the portion of the brain responsible for long-term memory storage, in adolescents. The researchers randomly selected 10 adolescents with alcohol use disorders to determine whether the hippocampal volumes in the alcoholic adolescents were less than the normal volume of 9.02 cm . An analysis of the sample data revealed that the hippocampal volume is approximately normal with no outliers and x = 8.18 cm and s = 0.7 cm . Conduct the appropriate test at the a = 0.01 level of significance. State the null and alternative hypotheses. Ho: H H1 : H (Type integers or decimals. Do not round.) Identify the t-statistic. to =(Round to two decimal places as needed.) Identify the P-value. P-value = (Round to three decimal places as needed.) Make a conclusion regarding the hypothesis. the null hypothesis. There sufficient evidence to claim that the mean hippocampal volume is cm .A credit score is used by credit agencies (such as mortgage companies and banks) to assess the creditworthiness of individuals. Values range from 300 to 850, with a credit soore over 700 considered to be a quality credit risk, According to a survey, the mean credit score is 701.1. A credit analyst wondered whether high-income individuals (incomes in excess of $100,000 per year) had higher credit scores. He obtained a random sample of 38 high-income individuals and found the sample mean credit score to be 719.8 with a standard deviation of 83.2. Conduct the appropriate test to determine if high-income individuals have higher credit scores at the a = 0.05 level of signicance. State the null and alternative hypotheses. \"0:\" l H1: p. Y (Type integers or decimals. Do not round.) Identify the t-statistic, t0 = (Round to two decimal places as needed) Identify the P-value. P-value = (Round to three decimal places as needed.) Make a conclusion regarding the hypothesis. W the null hypothesis. There 7 sufficient evidence to claim that the mean credit soore of high-income individuals is V The mean waiting time at the drive-through of a fast-food restaurant from the time an order is placed to the time the order is received is 86.2 seconds. A manager devises a new drive-through system 108.2 80.0 that he believes will decrease wait time. As a test, he initiates the new system at his restaurant and measures the wait time for 10 randomly selected orders. The wait times are provided in the table to 66.0 94.3 the right. Complete parts (a) and (b) below. 57.9 84.2 74.8 70.3 65.6 78.7 Click the icon to view the table of correlation coefficient critical values. (a) Because the sample size is small, the manager must verify that the wait time is normally distributed and the sample does not contain any outliers. The normal probability plot is shown below and the sample correlation coefficient is known to be r= 0.974. Are the conditions for testing the hypothesis satisfied? the conditions satisfied. The normal probability plot linear enough, since the correlation coefficient is than the critical value. In addition, a boxplot does not show any outliers. A Expected z-score 2- 60 75 90 -21 Time (sec) (b) Is the new system effective? Conduct a hypothesis test using the P-value approach and a level of significance of a = 0.05. First determine the appropriate hypotheses. 86.2 Hy: 86.2