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A research center estimates that no more than 40% of US adults eat breakfast every day. In a random sample of 250 US adults, 41.6% say they eat breakfast every day. At

Suppose the you have a left tailed test with a critical value , . The following value of the test statistics TS:  

Statistics professors have claimed that the average number of headaches during a semester of Statistics is 16. They sampled 22 students and found a sample mean of 13 and a sample standard deviation of 8. Do the data provide sufficient evidence to support the statistics professors claim? Test at 5% level of significance (use critical value method). Show your work. Do not submit your work here. Hold up your work to the webcam when you are done. Once you have submitted the test, you will upload your work on a separate assignment which will unlock after completing this test.

Identify the class width and the sample size used in the following frequency distribution: Class Cumulative frequency 50-53 5 54-57 13 58-61 23 62-65 32 66-69 35

I understand that I must show my work for questions 9-11 by holding up my paper to the webcam during the exam so that it is visibleand submitting the work on the “Test 3 (Submit Your Work)” assignment that becomes available when I complete this test.

A random sample of 94 light bulbs has a mean life of 548 hours with a standard deviation of 29 hours. Find the upper limit of a 94% confidence interval for the mean life of all light bulbs of this type.

The table shows the results of a survey that asked 1048 US adults whether they support or opposed a special tax on junk food (items like soda, chips, and candy). A person is selected at random from the sample. Find the probability that the person is not unsure or is a female. Support or Oppose Junk Food Tax Support Oppose Unsure Total Male 163 325 5 493 Female 233 300 22 555 Total 396 625 27 1048

Assume that for a newborn, the probability to be a boy is the same as the probability to be a girl. If you randomly select  10 newborns, the probability that exactly four of them are boys is:

I understand that I must show my work for questions 11-15 by holding up my paper to the webcam during the exam so that it is visibleand submitting the work on the “Practice Test (Submit Your Work)” assignment that becomes available when I complete this test.

In a typical day, 30% of people in the United States with internet access go online to get news. You randomly select eight people in the United States with internet access and ask them if they go online to get news. Find the probability that the number of them who say they don’t go online to get news is more than two but less than 6