6. When bonding teeth, orthodonists must maintain a dry filed. A new bonding adhesive has been developed to eliminate the neccessity of a try field. However, there is concern that the new bonding adhesive is not as strong as the current standard, a composite adhesive. Tests on a sample of 12 extracted teeth bonded with the new adhesive resulted in a mean breaking srength (after 24 hours) of x = 5.83 Mpa and a standard deviation of s = 0.49 Mpa. Orthodontists want to know if the true mean breaking strength is less than 6.46 Mpa, the mean braking strength of the composite adhesive. ******************************************************** MATH 533 Week 5 Quiz
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1. A group of professors investigated first-year college students’ knowledge of astronomy. One concept of interest was the Big Bang Theory of the creation of the universe. In a sample 0f 141 freshman students, 35 believed that the Big Bang Theory accurately described the creation of plantery systems. Baesd on this information, is it correct at the ι = 0.01 level of significance to state that more than 20% of all freshman college students believe the Big Bang theory describes the creation of planetary systems? 2. A study was conducted to evaluate the effectiveness of a new mosquito repellent designed by the U.S. Army to be applied as camouflage face paint. The repellent was applied to the forearms of 5 volunteers who then were exposed to 15 active mosquitos for a 10-hour period. The percentage of the forearm surface area protected from bites (called percent repellency) was calculated for each of the five volunteers. For one color of paint (loam), the following summary statistics were obtained: x =83%, s = 14%. Complete parts a and b. 3. A study of n = 110,000 first-time candidates for an exam found that the number of semester hours of college credit taken by the sampled candidate is