The weights of boxes produced by a factory are normally distributed with a standard deviation of σ = 2.5 kg. A quality control team takes a random sample of 36 boxes and measures their weights. The sample mean weight is found to be 50.2 kg. (a) Compute and interpret a 99% confidence interval for the true mean weight of the boxes. (b) How large a sample size is necessary if the width of the 99% confidence interval is to be at most 0.5 kg?

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018
18th Edition
ISBN:9780079039897
Author:Carter
Publisher:Carter
Chapter10: Statistics
Section10.3: Measures Of Spread
Problem 1GP
icon
Related questions
Question

Stats

The weights of boxes produced by a factory are normally distributed with a standard
deviation of σ = 2.5 kg. A quality control team takes a random sample of 36 boxes and
measures their weights. The sample mean weight is found to be 50.2 kg.
(a)
Compute and interpret a 99% confidence interval for the true mean
weight of the boxes.
(b) How large a sample size is necessary if the width of the 99% confidence
interval is to be at most 0.5 kg?
Transcribed Image Text:The weights of boxes produced by a factory are normally distributed with a standard deviation of σ = 2.5 kg. A quality control team takes a random sample of 36 boxes and measures their weights. The sample mean weight is found to be 50.2 kg. (a) Compute and interpret a 99% confidence interval for the true mean weight of the boxes. (b) How large a sample size is necessary if the width of the 99% confidence interval is to be at most 0.5 kg?
Expert Solution
steps

Step by step

Solved in 2 steps with 1 images

Blurred answer