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MATH 533 Week 5 Homework (New) Click Here to Buy the Tutorial For more course tutorials visit

1. A study of n = 90,000 first-time candidates for an exam found that the number of semester hours of college credit taken by the sampled candidates is summarized by x = 145.72 and s = 18.53. A professor claims that the true mean number of semester hours of college credit taken is 145.

2. A study of n = 59 hospital employees found that the number of latex gloves used per week by the sampled worker is summarized by x = 21.2 and s = 13.1. Let Âľ represent the mean number of latex gloves used per week by all hospital employees. Consider testing

3. The final scores of games of a certain sport were compared against the final point spreads established by oddsmakers. The difference between the game outcome and point spread (called a point-spread error) was calculated for 255 games. The sample mean and sample standard deviation of the point-spread errors are x = 1.3 and s = 12.9. Use this information to test the hypothesis that the true mean point-spread error for all games is larger than 0. Conduct the test at and interpret the result.

4. For the and observed significance level (p-value) pair, indicate whether the null hypothesis would be rejected. , p-value = 0.05

5. Consider a test of performed with the computer. The software reports a two-tailed p-value of 0.1032. Make the appropriate conclusion for each of the following situations.

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.

7. Whether planning for a new forest road to be used for tree harvesting, Planners must select the location to minimize tractor skidding distance. The skidding distances (in meters) were measured at 20 randomly selected road sites. The data are given below. A logger working on the road claims the mean skidding distance is atleast 418 meters. Is there sufficient evidence to refute this claim? Use α = 0.10.

8. Suppose 47 0f 110 randomly selected shoppers believe that “Made in the USA” means that 100% of labor and materials are from the United States. Let p represent the true proportion of consumers who believe “Made in the USA” means 100% of labor and materials are from the United States. Complete parts a through e.

9. The National Institute for Standards and Technology (NIST) mandates that for every 100 items scanned through the electronic checkout scanner at a retail store, no more than two should have an inaccurate price. A study of random items purchased at different California stores found that 3.3% had the wrong price. Assume that the study inclluded 841 randomly selected items. Complete parts a through e.

10. Suppose a consumer group rated 44 brands of toothpaste based on whether or not the brand an American Dental Association (ADA) seal verifying effective decay prevention. The results of a hypothesis test for the proportion of brands with the seal to the right. Complete parts a through c.

Math 533 week 5 homework