# Question

A catalog sales company promises to deliver orders placed on the Internet within three days. Follow-up calls to randomly selected customers show that a 95% confidence interval for the proportion of all orders that arrive on time is 88% ± 6%. What does this mean? Are the following conclusions correct? Explain.

(a) Between 82% and 94% of all orders arrive on time.

(b) 95% of all random samples of customers will show that 88% of orders arrived on time.

(c) 95% of all random samples of customers will show that 82% to 94% of orders arrived on time.

(d) We are 95% sure that between 82% and 94% of the orders placed by the customers in this sample arrived on time.

(e) On a randomly chosen day, we can be 95% confident that between 82% and 94% of the large volume of orders will arrive on time.

(a) Between 82% and 94% of all orders arrive on time.

(b) 95% of all random samples of customers will show that 88% of orders arrived on time.

(c) 95% of all random samples of customers will show that 82% to 94% of orders arrived on time.

(d) We are 95% sure that between 82% and 94% of the orders placed by the customers in this sample arrived on time.

(e) On a randomly chosen day, we can be 95% confident that between 82% and 94% of the large volume of orders will arrive on time.

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