I am interested in the number of hours my students spend studying during the week. I want to know if the average hours spent studying is more than 15 per week. To collect the data, I randomly sample 25 of my students and find that they study an average of l6.8 hours per week with a sample standard deviation of 1.2. a. Conduct a formal hypothesis that will answer my question. Use a = 0.10 and make the decision using a test statistic. Explain your decision using language that someone without statistical knowledge would understand. i.e. do not just state reject/fail to reject. b. What error could you have made? Explain the error in the context of the problem

Heather recently switched her primary doctor to one specializing in caring for elderly patients. On her new doctor's website, it says that the mean systolic blood pressure among elderly females is 115 millimeters of mercury (mmHg). Heather believes the value is actually higher. She bases her belief on a recently reported study of 13 randomly selected, elderly females. The sample mean systolic blood pressure was 125 mmHg, and the sample standard deviation was 25 mmHg. C Assume that the systolic blood pressures of elderly females are approximately normally distributed. Based on the study, at the 0.05 level of significance, can it be concluded that u, the population mean systolic blood pressure among elderly females, is greater than 115 mmHg? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places. (If necessary, consult a list of formulas.) (a) state the null hypothesis Ho and the alternative hypothesis H₁. 1 H₂ : 0…

John finds that there is a scholarship available to all persons scoring in the top 5 % on the ACT test. If the mean score on the ACT is 21 with a standard deviation of 4.7, what score does he need in order to qualify for the scholarship?

The average home in the US is expected to cost $240,000. A random sample of 56 homes sold this month showed average price of $232,000. Assume you have access to this data. We are interested in determining cost if the cost of average home has decreased this month. If the test statistic is -1.66 what is the p-value?

A successful basketball player has a height of 6 feet 11 ​inches, or 211 cm. Based on statistics from a data​ set, his height converts to the z score of 5.17. How many standard deviations is his height above the​ mean?

To celebrate the end of final exams you and friends head to a favorite downtown restaurant. You find a street parking spot with a maximum of two hours. If you stay longer than two hours, you risk having your car towed away. No one has a watch or cellphone but you remember that the average time you spent at the same restaurant over your previous 16 visits is 1.5 hours, and you estimate the sample standard deviation to be about 20 minutes. You also need to factor in that it takes 8 minutes to walk to the restaurant and 8 minutes to walk back to your car (you are very certain about these two durations). (a) One of your friends is really worried that you won’t get back to the car in time and so the car might be towed away! Does your friend have good reason to be worried? Test at a 5% significance level whether the mean total time will be less than two hours. (b) You decide to leave the car parked at the street spot but it gets towed. What type of error have you committed?