A recent survey showed that from a sample of 500 packages delivered by a Postal Service, 480 were delivered on time. a. Construct a 95% confidence interval for the proportion of all packages that are delivered on time by the Postal Service. b. The manager of the Postal Services claims that 98% of their mail are delivered on time. Test at the 1% significance level to determine whether the true proportion is less than 98%.

A recent survey showed that from a sample of 500 packages delivered by a Postal Service, 480 were delivered on time. a. Construct a 95% confidence interval for the proportion of all packages that are delivered on time by the Postal Service. b. The manager of the Postal Services claims that 98% of their mail are delivered on time. Test at the 1% significance level to determine whether the true proportion is less than 98%.

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Description: A recent survey showed that from a sample of 500 packages delivered by a Postal Service, 480 were delivered on time.a. Construct a 95% confidence interval for the proportion of all packages that are delivered on time by the Postal Service.b. The mana

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.6: Summarizing Categorical Data

Problem 30PPS

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