The number of minutes for app engagement by a tablet user follows a normal distribution with = 8.2 minutes, and o = 1 minute. Suppose, we take a sample of 60 tablet users. W (a) What are the mean and standard deviation of the sampling distribution of the sample mean? (b) Find the 90th percentile for the sample mean time for app engagement for a tablet user. Interpret this value in a complete sentence. (c) Find the probabilities that the sample mean is between ±1 standard deviation, ±2 standard deviations, and ±3 standard deviations. (d) Is there a different way to do part (c) that involves not using R, and not using any form of calculations?

The number of minutes for app engagement by a tablet user follows a normal distribution with = 8.2 minutes, and o = 1 minute. Suppose, we take a sample of 60 tablet users. W (a) What are the mean and standard deviation of the sampling distribution of the sample mean? (b) Find the 90th percentile for the sample mean time for app engagement for a tablet user. Interpret this value in a complete sentence. (c) Find the probabilities that the sample mean is between ±1 standard deviation, ±2 standard deviations, and ±3 standard deviations. (d) Is there a different way to do part (c) that involves not using R, and not using any form of calculations?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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