# MGMT 650 MGMT650 Quiz 3 Answers (UMUC)

MGMT 650 Quiz 3 (UMUC)

A nonprofit company concemced with the school dropout rates in a nearby state has designed a tutoring program aimed at students between 16 to 18 years old. The high school dropout rate in the state for the year 2000 was 9.4%. One school district, who adopted the use of the nonprofit's tutoring program and whose dropout rate has always been very close to the state average, reported in 2004 that 126 of their 1758 students dropped out. Is their experience evidence that the tutoring program has been effective? Explain.Â

What are the null and alternative hypotheses?Â

What is the value ofthe test statistic?

What is the P-value ofthe test statistic?Â

Is their experience evidence that the tutoring program has been effective? Explain.Â

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A company is developing a new high-performance wax for cross country ski racing. In order to justify the price marketing wants, the wax needs to be very fast. Specifically, the mean time to finish their standard test course should be less than 55 seconds for a former Olympic champion. To test it, the champion will ski the course 8 times. The champion's times (selected at random) are 58.4, 62.3, 46.1, 50.5, 46.9, 45.3, 53.4, and 44.5 seconds to complete the test course. Complete parts a and b below.Â

a) Should they market the wax? Assume the assumptions and conditions for appropriate hypothesis testing are met for the sample. Assume a= 0.05. What are the null and alternative hypotheses? Choose the correct answer below.Â

b) Suppose they decide not to market the wax after the test, but it turns out that the wax really does lower the champion's average time to less than 55 seconds. What kind of error have they made? Explain the impact to the company of such an error.Â

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A feed supply company has developed a special feed supplement to see if it will promote weight gain in livestock. Their researchers report that the 77 cows studied gained an average of 56 pounds and that a 95% confidence interval for the mean weight gain this supplement produces has a margin of error of Â± 11 pounds. Five staff members from the marketing department were chosen to interpret the results. Answer parts (a) through (e).Â

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For each of the following scenarios, say whether the data should be treated as independent or paired samples. Explain briefly. Ifpaired, explain what the pairing involves.

a) An efficiency expert claims that a new ergonomic desk chair makes typing at a computer terminal easier and faster. To test it, 15 volunteers are selected. Using both the new chair and their old chair, each volunteer types a randomly selected passage for 2 minutes and the number of correct words typed is recorded. Choose the correct answer below.Â

b) A developer wants to know if the houses in two different neighborhoods have the same mean price. She selects 10 houses from each neighborhood at random and tests the null hypothesis that the means are equal. Choose the correct answer below.Â

c) A manager wants to know if the mean productivity of two workers is the same. For a random selection of 30 hours in the past month, he compares the number of items produced by each worker in that hour. Choose the correct answer below.Â

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A developer wants to know if the houses in two different neighborhoods were built at roughly the same time. She takes a random sample of six houses from each neighborhood and finds their ages from local records. The accompanying table shows the data for each sample (in years). Assume that the data come from a distribution that is Normally distributed. Complete parts a through c below.Â

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A developer wants to know if the houses in two different neighborhoods were built at roughly the same time. She takes a random sample of six houses from each neighborhood and finds their ages from local records. The accompanying table shows the data for each sample (in years). Complete parts a through e below.Â

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A company is criticized because only 18 of46 executives at a local branch are women. The company explains that although this proportion is lower than it might wish, it's not a surprising value given that only 42% of all its employees are women. The company has more than 500 executives worldwide. Test an appropriate hypothesis and state the conclusion.Â

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A market analyst wants to know ifthe new website he designed is showing increased page views per visit. A customer is randomly sent to one of two different websites, offering the same products, but with different designs. The accompanying table shows the data from five randomly chosen customers from each website. Assume that the data come from a distribution that is Normally distributed. Complete parts a through c below.Â