A catalog sales company promises to deliver orders placed on the Internet within three business days.Follow-up calls to a few randomly selected customers show that a 95% confidence interval for the proportion of all orders that arrive on time is 88&nbsp;a) What is the meaning of this? Are these findings accurate? Explain.&nbsp;b) 95% of all random samples of customers will show that 88% of orders arrive on time.&nbsp;c) 95% of all random samples of customers will show that 82% to 94% of orders arrive on time.&nbsp;d) We are 95% sure that between 82% and 94% of the orders placed by the sampled customers arrived on time.&nbsp;e) On 95% of the days, between 82% and 94% of the orders will arrive on time.

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A catalog sales company promises to deliver orders placed on the Internet within three business days.Follow-up calls to a few randomly selected customers show that a 95% confidence interval for the proportion of all orders that arrive on time is 88&amp;nbsp;a) What is the meaning of this? Are these findings accurate? Explain.&amp;nbsp;b) 95% of all random samples of customers will show that 88% of orders arrive on time.&amp;nbsp;c) 95% of all random samples of customers will show that 82% to 94% of orders arrive on time.&amp;nbsp;d) We are 95% sure that between 82% and 94% of the orders placed by the sampled customers arrived on time.&amp;nbsp;e) On 95% of the days, between 82% and 94% of the orders will arrive on time.

Brighton · Accepted Answer

a) Incorrect. This implies certainty.  b) Incorrect. Different samples will give different results. Many fewer than 95% will have 88% on-time orders.  c) Incorrect. The interval is about the population proportion, not the sample proportion in different samples.  d) Incorrect. In this sample, we know 88% arrived on time  e) Incorrect. The interval is about the parameter, not about the days.

A catalog sales company promises to deliver orders placed on the Internet within 3 days. Follow-up calls to a few randomly selected customers show tha

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