Help with these from chapter 19 assignment, data table uploaded
A college entrance exam company determined that a score of 25 on the mathematics portion of the exam suggests that a student is ready for college-level mathematics. To achieve this goal, the company recommends that students take a core curriculum of math courses in high school. Suppose a random sample of 200 students who completed this core set of courses results in a mean math score of 25.6 on the college entrance exam with a standard deviation of 3.8. Do these results suggest that students who complete the core curriculum are ready for college-level mathematics? That is, are they scoring above 25 on the math portion of the exam? Complete parts a) through d) below. a) State the appropriate null and alternative hypotheses. Fill in the correct answers below. The appropriate null and alternative hypotheses are H0: |:1| El El versus H1: |:1| El El. 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 21 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 = 8.02 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.)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 score over 700 considered to be a quality credit risk. According to a survey. the mean credit score is 704.2. 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 42 high-income individuals and found the sample mean credit score to be 719.1 with a standard deviation of 80.5. 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. (Type integers or decimals. Do not round.) It has long been stated that the mean temperature of humans is 98.60F. However, two researchers currently involved in the subject thought that the mean temperature of humans is less than 98.6F. They measured the temperatures of 67 healthy adults 1 to 4 times daily for 3 days, obtaining 300 measurements. The sample data resulted in a sample mean of 98.3F and a sample standard deviation of 1F. Use the P-value approach to conduct a hypothesis test to judge whether the mean temperature of humans is less than 98.6F at the a = 0.01 level of signicance. State the hypotheses. HO: u = 98.6F H1: u
