A researcher wants to calculate a 95% confidence interval for the unknown trueproportion of defective resistors off an assembly line. They take a random sample of 50resistors, and find that 2 of them are defective. Are the needed assumptions for theconfidence interval satisfied?No, because the sample size is still too small.No, because they should be use the T distributionNo, because they took a random sampleO Yes, because the sample size is larger than 30

The sample size for the test is 50. Here, the confidence interval for proportion is needed.

Answered: A researcher wants to calculate a 95%…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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A random sample of 100 students is taken from a larger population of students in a multi-lecture course and the sample mean (average) of their final grades is found to be 62.25. Suppose that the population standard deviation is known to be 3. Which of the following is correct? A 90% Z confidence interval for the true population mean that is calculated from this sample data of 100 students will be wider than a 95% Z confidence interval for the true population mean that is calculated from this sample data of 100 students. b. A 95% Z confidence interval for the true population mean that is calculated from this sample data of 100 students will be narrower than a 90% Z confidence interval for the true population mean that is calculated from this sample data of 100 students. c. A 90% Z confidence interval for the true population mean that is calculated from this sample data of 100 students would be narrower than a 90% Z confidence interval for the true population mean that is…

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