Marcelina has over 500 songs on her mobile phone, and she wants to estimate the average length of the songs (in minutes). She takes an SRS of 28 songs on her phone and calculates a sample mean of 3.4 minutes and a standard deviation of 0.72 minutes. The song lengths in the sample were roughly symmetric with no clear outliers. Based on this sample, which of the following is a 99% confidence interval for the mean length (in minutes) of the songs on her phone? Choose 1 answer: 3.4 + 2.576(0.72) 3.4 +2.77(0.72) 0.72(0.28) C. 3.4+ 2.576 28 0.72 D. 3.4 + 2.576 28

Marcelina has over 500 songs on her mobile phone, and she wants to estimate the average length of the songs (in minutes). She takes an SRS of 28 songs on her phone and calculates a sample mean of 3.4 minutes and a standard deviation of 0.72 minutes. The song lengths in the sample were roughly symmetric with no clear outliers. Based on this sample, which of the following is a 99% confidence interval for the mean length (in minutes) of the songs on her phone? Choose 1 answer: 3.4 + 2.576(0.72) 3.4 +2.77(0.72) 0.72(0.28) C. 3.4+ 2.576 28 0.72 D. 3.4 + 2.576 28

Name: Marcelina has over 500 songs on her mobile phone, and she wants to es
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Description: Marcelina has over 500 songs on her mobile phone, and she wants to estimate the average length of the songs(in minutes). She takes an SRS of 28 songs on her phone and calculates a sample mean of 3.4 minutes and astandard deviation of 0.72 minutes. T

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

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