Math Problem Statement
The lifetime of a certain brand of electric light bulb is known to have a standard deviation of 54 hours. Suppose that a random sample of 50 bulbs of this brand has a mean lifetime of 486 hours. Find a 95% confidence interval for the true mean lifetime of all light bulbs of this brand. Then give its lower limit and upper limit.
Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.
Solution
Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Statistics
Confidence Intervals
Normal Distribution
Formulas
Confidence interval for the mean: CI = x̄ ± Zα/2 * (σ / √n)
Theorems
Central Limit Theorem
Suitable Grade Level
College
Related Recommendation
Calculate 90% Confidence Interval for Mean Lifetime of Lightbulbs
Calculating 95% and 99% Confidence Intervals for Standard Deviation of Electric Bulb Lifetimes
Calculate 90% Confidence Interval for Variance and Standard Deviation
Calculate 90% Confidence Interval for Mean Lifespan of Batteries
Calculate 90% Confidence Interval for Mean with Population Standard Deviation