SOLUTION: A manufacturer receives an order for fluorscent light bulbs. The order requires that the bulbs have a mean life span of 550 hours. The manufacturer selects a random sample of 25 fl
Algebra ->
Probability-and-statistics
-> SOLUTION: A manufacturer receives an order for fluorscent light bulbs. The order requires that the bulbs have a mean life span of 550 hours. The manufacturer selects a random sample of 25 fl
Log On
Question 279758: A manufacturer receives an order for fluorscent light bulbs. The order requires that the bulbs have a mean life span of 550 hours. The manufacturer selects a random sample of 25 fluorescent light bulbs and finds that they have a mean life span of 545 hours with a standard deviation of 15 hours. Is the manufacturer making acceptable light bulbs? Defend your answer. use a 95% confidence level. Assume the data is normally distributed.
Please show work. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A manufacturer receives an order for fluorscent light bulbs.
The order requires that the bulbs have a mean life span of 550 hours.
The manufacturer selects a random sample of 25 fluorescent light bulbs and finds that they have a mean life span of 545 hours with a standard deviation of 15 hours. Is the manufacturer making acceptable light bulbs? Defend your answer. use a 95% confidence level. Assume the data is normally distributed.
----------------------
sample mean = 545
standard error = E = invT(0.975.24)*15/sqrt(25) = 6.1917
--------------------
95% CI: 545-6.1917 < u < 545+6.1917
95% CI: 538.81 < u < 551.19
===============================
Cheers,
Stan H.
(