Reference no: EM131008567
1. More hypotheses. Write the null and alternative hypotheses to test each of the following situations.
a) A business magazine article reports that, in 1990, 35% of CEOs had an MBA degree. Has the percentage changed?
b) Recently, 20% of cars of a certain model have needed costly transmission work after being driven between 50,000 and 100,000 miles. The car manufacturer hopes that the redesign of a transmission component has solved this problem.
c) A market researcher for a cola company decides to field test a new flavor soft drink, planning to market it only if he is sure that over 60% of the people like the flavor.
2. Deliveries. The clothing company in Exercise 21a looks at a sample of delivery reports. They test the hypoth- esis that 90% of the deliveries are on time against the alterna- tive that greater than 90% are on time and find a P-value of 0.22. Which of these conclusions is appropriate?
a) There's a 22% chance that 90% of the deliveries are on time.
b) There's a 78% chance that 90% of the deliveries are on time.
c) There's a 22% chance that the sample they drew shows the correct percentage of on-time deliveries
d) There's a 22% chance that natural sampling variation could produce a sample with an observed proportion of on-time deliveries such as the one they obtained if, in fact, 90% of deliveries are on time.
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The cecil booker vending company changed its metho
: Prepare the 2011-2010 comparative income statements beginning with income from continuing operations. Include per share amounts.
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Problem regarding the house sales
: The realty company in Exercise 21b looks at a recent sample of houses that have sold. On testing the null hypothesis that 50% of the houses take more than three months to sell against the hypothesis that more than 50% of the houses take more than ..
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Pyramid construction company has used the completed contract
: Prepare the 2011-2010 comparative statements of shareholders' equity. (Hint: The 2009 statements reported retained earnings of $36,000. This is $60,000 - [$60,000 × 40%].
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What is the value of the correlation coef?cient
: Predict the volume of cerebral grey matter at age 2 to 5 years for a child whose head circumference z score at age 12 months was 1.8. Explain why it would not be a good idea to use the least-squares line to predict the volume of grey mat- ter..
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Correct percentage of on-time deliveries
: There's a 22% chance that the sample they drew shows the correct percentage of on-time deliveries There's a 22% chance that natural sampling variation could produce a sample with an observed proportion of on-time deliveries such as the one they obt..
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How are confidence intervals calculated
: A 95% confidence interval is not so much a statement about any particular interval, such as (79.3, 80.7), but pertains to what would happen if a very large number of like intervals were to be constructed. How are confidence intervals calculated
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Prepare the journal entry to record the change in accounting
: Assume that Weihrich used FIFO before 2011, and then in 2011 decided to switch to average cost. Prepare the journal entry to record the change in accounting principle and briefly describe any other steps Weihrich should take to appropriately report t..
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Proportion of houses
: A realty company recently announced that the proportion of houses taking more than three months to sell is now greater than 50%. A financial firm's accounting reports that after improvements in their system, they now have an error rate below 2%.
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Reject the null hypothesis
: For each of the following situations, state whether a Type I, a Type II, or neither error has been made. a) A test of H0: m = 25 vs. HA: m 7 25 rejects the null hypothesis. Later it is discovered that m = 24.9. b) A test of H0: p = 0.8 vs. HA: p 6 0..
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