In a sample of 80 light bulbs, the mean lifetime was 1217 hours. Assume the population standard

Question:

In a sample of 80 light bulbs, the mean lifetime was 1217 hours. Assume the population standard deviation is 52 hours.

a. Find a 95\% confidence interval for the mean lifetime of this type of light bulb.

b. Find a $98 \%$ confidence interval for the mean lifetime of this type of light bulb.

c. An engineer claims that the mean lifetime is between 1208 and 1226 hours. With what level of confidence can this statement be made?

Fantastic news! We've Found the answer you've been seeking!

Step by Step Answer:

Related Book For book-img-for-question

Statistics For Engineers And Scientists

ISBN: 9780073107677

6th Edition

Authors: William Navidi

See More Books

Question Posted: Feb 04, 2024 05:00 AM

See More Questions

In a sample of 100 steel wires the average breaking strength is 50 kN, with a standard deviation of 2 kN. a. Find a 95% confidence interval for the mean breaking strength of this type of wire. b....
HFI sells bedroom furniture to hotel chains, including beds, nightstands, television tables, desks and chests of drawers. Hotel room furniture is often exposed to hard use and often must be replaced...
In a sample of 80 ten-penny nails, the average weight was 1.56 g and the standard deviation was 0.1 g. a. Find a 95% confidence interval for the mean weight of this type of nail. b. Find a 98%...
A data analyst decided to do all design work from home and wants to create a home office. The analyst needs a new computer for $1,900 and printer/scanner for $250. A vendor offers a financing option...
An observer at sea level does not hear an aircraft flying at 12000 ft standard altitude until it is 5 statute miles past her. Estimate the aircraft speed in ft/sec. V, Ma observer 12000 ft 5 miles...
What department is usually responsible for a direct labor rate variance? What department is usually responsible for a direct labor efficiency variance? Explain.
Most developed economies have well-developed road and highway networks. From time to time new highways are built to relieve congested cities, but by and large most developed countries are not...
Helen and Gerald incorporated Zion Ltd in 2008. Zion Ltd manufactures and sells wine barrels in Margaret River, Western Australia. The business had been successful until late 2013 when Helen and...
i need help with this question with an explanation thanks! 7) Large Co. pays its employees $20,000 gross salary each week. 30% of salary is withheld for income taxes and 5% is withheld to pay Social...
Refer to Exercise 7. a. Find a $90 \%$ upper confidence bound for the mean lifetime. b. Someone says that the mean lifetime is less than 1220 hours. With what level of confidence can this statement...
A sample of 114 patients were given a drug to lower cholesterol. A 95\% confidence interval for the mean reduction in cholesterol (in $\mathrm{mmol} / \mathrm{L}$ ) was $(0.88,1.02)$. a. What was...
The Medequip Company produces precision medical diagnostic equipment at two factories. Three medical centers have placed orders for this months production output. The table below shows what the cost...
K Perform the indicated operation. 38 + 3 5 8 + 12 5 12 = (Type an integer or a fraction. Simplify your answer.)
How do synchronization techniques differ between shared-memory and message-passing concurrency models?
Discuss how both motivation and a lack of motivation can impact different criminal justice organizations. What theories can be utilized to explain how criminal justice leaders can better motivate...
Describe an experiment that could be performed by scientists to examine the effectiveness of a new vaccine on one of the eukaryotic species from part A. 1. Describe how vaccines work to prevent viral...
Write a function to determine if two strings are anagrams of each other. Anagrams are strings that contain the same characters but in a different order.
The following are several situations involving compound interest. Required Using the appropriate table, solve each of the following: 1. Hope Dearborn invests $40,000 on January 1, 2007 in a savings...
Suppose that a flow network G = (V, E) violates the assumption that the network contains a path s t for all vertices V. Let u be a vertex for which there is no path s u t. Show that there must...
In a support system in the U.S. space program, a single crucial component works only 85% of the time. In order to enhance the reliability of the system, it is decided that 3 components will be...
The purpose of the study The Incorporation of a Chelating Agent into a Flame Retardant Finish of a Cotton Flannelette and the Evaluation of Selected Fabric Properties, conducted at Virginia Tech, was...
Personnel in the Materials Engineering Department at Virginia Tech conducted an experiment to study the effects of environmental factors on the stability of a certain type of copper-nickel alloy. The...
Can you elaborate on the considerations and trade-offs involved in selecting appropriate DynamoDB storage types, including provisioned capacity, on-demand capacity, and DynamoDB Accelerator (DAX),...
A small rubber ball is launched by a compressed - air cannon from ground level with an initial speed of 1 2 . 4 1 2 . 4 m / / s directly upward. Choose upward as the positive direction in your...
Given the basis 2 2 for R3, use the Gram-Schmidt pro- cess to obtain an orthonormal basis {u, u2, u3}. (4pts) (6pts) (8pts) Ans: u = u2= uz=

In a sample of 80 light bulbs, the mean lifetime was 1217 hours. Assume the population standard

Question:

Step by Step Answer:

To calculate confidence intervals for the mean lifetime of the light bulbs we can use the concept of the tdistribution since the population standard deviation is not known and the sample size is relat...View the full answer

Statistics For Engineers And Scientists

Students also viewed these Business questions