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Point estimates and margins of error

Please help with the following problems. Provide step by step solutions.

According to Thomson Financial, through January 25, 2006, the majority of companies reporting profits had beaten estimates (Business Week, February 6, 2006). A sample of 162 companies showed 104 beat estimates, and 29 fell short.

a. What is the point estimate of the proportion that fell short of estimates ?

b. Determine the margin of error and provide a 95% confidence interval for the proportion that beat estimates.

c. How large a sample is needed if the desired margin of error is .05?

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According to Thomson Financial, through January 25,2006, the majority of companies reporting profits had beaten estimates(Business Week, February 6, 2006). A SAMPLE OF 162 companies showed 104 beat estimates, and 29 fell short.

a. What is the point ...

Solution Summary

The following posting helps with problems involving point estimates and margins of error. Calculations involve point estimates, margin of error and sample size.

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