A drug company developed a drug D that they believe will reduce cholesterol in men.  It is known that the mean cholesterol level of males between the ages of 20 and 74 years old living in the United States is μ = 211 mg (per 100 ml), with a standard deviation of σ = 46 mg (per 100 ml).  To test this belief, the company recruited n=1000 males between the ages of 20 and 74 years old living in the United States and gave them drug D over the course of 3 months.  At the end of the 3 month drug treatment, cholesterol level was tested for these n=1000 study participants.  Their mean cholesterol level was found to be MD = 200 ml (per 100 ml).  Perform a z-test by answering the questions below.  Use an alpha-level of α=.05.

One of the measurements used to determine the health of a person's lungs is the amount of air a person can exhale under force in one second. This is called forced expiratory volume in one second, and is abbreviated FEV,. Assume the mean FEV, for 10-year-old boys is 2.1 liters that the population standard deviation is o =0.2. A random sample of 53 10-year-old boys live in a community with high levels of ozone pollution are found to have a sample mean FEV, of 2.09 liters. Can you conclude that the mean FEV, in the high-pollution community differs from 2.1 liters? (A) Yes (B) No

A manufacturer of bolts has a quality control policy that requires it to destroy any bolts that are more than 2 standard deviations from the mean. The quality control engineer knows that the bolts coming off the assembly line have a mean length of 8cm with a standard deviation of 0.05 cm. For what length will a bolt be destroyed?

It takes an average of 14.5 minutes for blood to begin clotting after an injury. An EMT wants to see if the average will increase if the patient is immediately told the truth about the injury. The EMT randomly selected 70 injured patients to immediately tell the truth about the injury and noticed that they averaged 16.3 minutes for their blood to begin clotting after their injury. Their standard deviation was 4.75 minutes. What can be concluded at the the α = 0.10 level of significance? a. For this study, we should use [Select an answer b. The null and alternative hypotheses would be: Ho: ? Select an answer H₁: ? Select an answer ✓ c. The test statistic ? = (please show your answer to 3 decimal places.) d. The p-value = (Please show your answer to 4 decimal places.) e. The p-value is ? ✓ a f. Based on this, we should [Select an answer the null hypothesis. g. Thus, the final conclusion is that ... O The data suggest the populaton mean is significantly greater than 14.5 at a = 0.10, so…

From generation to generation, the mean age when smokers first start to smoke varies. However, the standard deviation of the age when smokers first start to smoke remains constant at around 2.1 years. The American Lung Association claims that the mean age when smokers first start to smoke is at least 17. A survey of 40 randomly selected smokers of this generation was done and it was found that the mean age when smokers first started to smoke was 18.1. Is there enough evidence to reject the claim?    Describe what a Type I error is for this situation.   Describe what a Type II error is for this situation.

It takes an average of 14 minutes for blood to begin clotting after an injury.  An EMT wants to see if the average will change if the patient is immediately told the truth about the injury. The EMT randomly selected 43 injured patients to immediately tell the truth about the injury and noticed that they averaged 12.5 minutes for their blood to begin clotting after their injury. Their standard deviation was 3.1 minutes. What can be concluded at the the αα = 0.01 level of significance? For this study, we should use     The null and alternative hypotheses would be:       H0:H0:                   H1:H1:               The test statistic     =  (please show your answer to 3 decimal places.) The p-value =  (Please show your answer to 4 decimal places.) The p-value is     αα Based on this, we should      the null hypothesis. Thus, the final conclusion is that ... The data suggest the population mean is not significantly different from 14 at αα = 0.01, so there is statistically significant…

Low-density lipoprotein, or LDL, is the main source of cholesterol buildup and blockage in the arteries. This is why LDL is known as "bad cholesterol." LDL is measured in milligrams per deciliter of blood, or mg/dL. In a population of adults at risk for cardiovascular problems, the distribution of LDL levels is normal, with a mean of 123 mg/dL and a standard deviation of 41 mg/dL. If an individual's LDL is at least 1 standard deviation or more above the mean, he or she will be monitored carefully by a doctor. What percentage of individuals from this population will have LDL levels 1 or more standard deviations above the mean? Use the 68–95–99.7 rule. (Enter your exact answer as a whole number.) percentage %