A consumer organization wants to estimate the actual tread wear index of a brand name of tires that claims "graded150"on the sidewall of the tire. A random sample ofn=19indicates a sample mean tread wear index of148.7and a sample standard deviation of22.3.Complete parts (a) through (c).a.Assuming that the population of tread wear indexes is normally distributed, construct a90%confidence interval estimate of the population mean tread wear index for tires produced by this manufacturer under this brand name. nothing≤μ≤nothing(Round to two decimal places as needed.)

The summary of the statistics is, x¯=148.7,s=22.3,n=19 The degree of freedom is, df=n-1 =19-1 =18 Critical values: By using the t-tables, the critical value at 10% level of significance with df = 18 for a two tailed t -distribution is, t0.10/2=±1.734The 90% confidence interval estimate of the population mean tread wear index for tires produced by this manufacturer under this brand name is, Therefore, the required confidence interval is,

Answered: A consumer organization wants to…

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

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.5: Comparing Sets Of Data

Problem 13PPS

See similar textbooks

Related questions

Concept explainers

Question

A consumer organization wants to estimate the actual tread wear index of a brand name of tires that claims "graded

150"

on the sidewall of the tire. A random sample of

n=19

indicates a sample mean tread wear index of

148.7

and a sample standard deviation of

22.3.

Complete parts (a) through (c).

a.	Assuming that the population of tread wear indexes is normally distributed, construct a 90% confidence interval estimate of the population mean tread wear index for tires produced by this manufacturer under this brand name.

nothing≤μ≤nothing

(Round to two decimal places as needed.)

Features Features Normal distribution is characterized by two parameters, mean (µ) and standard deviation (σ). When graphed, the mean represents the center of the bell curve and the graph is perfectly symmetric about the center. The mean, median, and mode are all equal for a normal distribution. The standard deviation measures the data's spread from the center. The higher the standard deviation, the more the data is spread out and the flatter the bell curve looks. Variance is another commonly used measure of the spread of the distribution and is equal to the square of the standard deviation.

Expert Solution

Trending now

This is a popular solution!

Step by step

Solved in 2 steps with 2 images

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

$Point Estimation, Limit Theorems, Approximations, and Bounds$

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.

Recommended textbooks for you

Glencoe Algebra 1, Student Edition, 9780079039897…

Algebra

ISBN:

9780079039897

Author:

Carter

Publisher:

McGraw Hill