It is known the average number of people who visit the ER is 145.   A sample is collected of 20 hospitals.  The average number of people who came to the ERs per day was 162, with a sample standard deviation of 45.   Conduct a hypothesis test based on the research question presented.  Using an alpha of .05 Fail to reject the null hypothesis Reject the alternative hypothesis Reject the null hypothesis Fail to reject the alternative

When you purchased your car, the dealer told you that your average gas mileage on your car was 30mpg, but you suspect that is might be lower than that. You conduct a sample over 30 days, and find that your sample average is only 28 mpg, with a standard deviation of 8.2 mpg. You conduct a hypothesis test, and find a P-value of 9.6%. What are your conclusions? Use an a level of 5% O Reject H, and accept H4. You have strong evidence that your car does get less than 28 mpg, on average. O Accept H.. You have strong evidence that your car gets 28 mpg, on average. O Reject H4. You have strong evidence that your car gets more than 28 mpg, on average. O Fail to reject Ho. You do not have strong evidence that your car gets less than 28 mpg, on average.

Calculate z scores from two samples The tallest living man at one time had a height of 252 cm. The shortest living man at that time had a height of 30.3 cm. Heights of men at that time had a mean of 170.25 cm and a standard deviation of 8.47 cm. Answer Z score for the tallest man Z-score for the shortest men

Advertisements claim the average nicotine content of a certain kind of cigarette is 0.30 mg. suspecting that this figure is too low; a consumer protection service takes a random sample of 15 of these cigarettes from different production lots and find their nicotine content has a mean of 0.33mg with a standard deviation of 0.18 mg. Is the advertisements claim true? use alpha=0.05

A clinical researcher performs a clinical trial on 6 patients to determine whether a drug treatment has an effect on serum glucose. The sample mean glucose of the patients before and after the treatment are summarized in the following table. The sample standard deviation of the differences was 10.     Sample mean glucose (mg/dL) Before treatment 105 After treatment 99     What type of hypothesis test should be performed?_______ select (left-tailed z-test, Paired t-test, two-tailed z-test, unpaired t-test)   What is the test statistic?_______ (Ex: 0.123)   What is the number of degrees of freedom? _______ (Ex: 25)   Does sufficient evidence exist to support the claim that the drug treatment has an effect on serum glucose at the α=0.01 significance level? ______ select (no or yes)

10. Gravetter/Wallnau/Forzano, Essentials - Chapter 9 - End-of-chapter question 15 Weinstein, McDermott, and Roediger (2010) report that students who were given questions to be answered while studying new material had better scores when tested on the material compared to students who were simply given an opportunity to reread the material. In a similar study, an instructor in a large psychology class gave one group of students questions to be answered while studying for the final exam. The overall average for the exam was u = 73.4, but the n = 16 students who answered questions had a mean of M = 78.3 with a standard deviation of s = 8.4. For this study, did answering questions while studying produce significantly higher exam scores? Use a one-tailed test with a = .01 and the Distributions tool to help. (Round your answers to three decimal places, when needed.) t Distribution Degrees of Freedom = 21 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 SM %3D t-critical %3D

Daily Driving The average number of miles a person drives per day is   24. A researcher wishes to see if people over age 60 drive less than 24  miles per day. She selects a random sample of 32 drivers over the age of   60 and finds that the mean number of miles driven is 22.9. The population standard deviation is 3.1 miles. At α=0.05, is there sufficient evidence that those drivers over   60 years old drive less than 24 miles per day on average? Assume that the variable is normally distributed. Use the P-value method with a graphing calculator. Find the P-value. Round it to four decimal places.

We want to conduct a hypothesis test of the claim that for middle-aged adults the population mean of their cholesterol levels is less than 198.9 mgdL. We choose a random sample of such levels. The sample has a mean of 195.9 mgdL and a standard deviation of 19.5 mgdL. For each of the following sampling scenarios, choose an appropriate test statistic for our hypothesis test on the population mean. Then calculate that statistic. Round your answers to two decimal places. (a) The sample has size15, and it is from a population with a distribution about which we know very little.       z =       t =       It is unclear which test statistic to use.   (b) The sample has size 19, and it is from a normally distributed population with an unknown standard deviation.       z =       t =        It is unclear which test statistic to use.

The state of CT claims that the average time on death row is 15 years. A random survey of 75 death row inmates revealed that the average length of time on death row is 16.6 years with a standard deviation of 5.8 years. Conduct a hypothesis to test the state of CT's claim. t test mean two tail test   p value = ____________ What is the decision?

Newborn Elephant Weights Newborn elephant calves usually weigh between 200 and 250 pounds-until October 2006, when an Asian elephant at the Houston (Texas) Zoo gave birth to a male calf weighing in at a whopping 384 pounds! Mack (like the truck) is believed to be the heaviest elephant calf ever born at a facility accredited by the Association of Zoos and Aquariums. If, Indeed, the mean weight for newborn elephant calves is 235 pounds with a standard deviation of 43 pounds, what is the probability of a newborn weighing at least 384 pounds? Assume that weights of newborn elephants are normally distributed. Round z-value calculations to 2 decimal places and final answer to at least 4 decimal places. The probability that a newborn elephant weighs at least 384 pounds is