SOLUTION: A manufacturer of a certain brand of wristwatch claims that the mean life expectancy of the battery of the watch is 48 months. A researcher wants to validate this claim so he chose

Question 1179067: A manufacturer of a certain brand of wristwatch claims that the mean life expectancy of the battery of the watch is 48 months. A researcher wants to validate this claim so he chose a sample of 64 watches and noted that their mean life expectancy is 45 months with a standard deviation of two months. At α = 0.05, can you conclude that the mean life expectancy is less than 48 months? Prove your answer.

Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!


Hi
population: µ  = 48mo    Sample(n=64): µ  = 45mo  and s = 2mo
Ho:  µ  = 48
Ha:  µ  < 48
Confidence Interval .05:  one-tailed t-test: t(df63) = |t-value|> 1.6694 Reject Ho

t-value =  = -12
|-12| > 1.6694 
Reject Ho, Evidence shows mean life expectancy is < 48 months

Wish You the Best in your Studies.

RELATED QUESTIONS
A manufacturer of automobile batteries claims that the distribution of the lengths of... (answered by stanbon)

Need to know how to solve the following: The life expectancy of Timely brand watches... (answered by stanbon)

A mobile phone manufacturer is promoting a new mobile because of its excellent battery... (answered by Boreal)

A wristwatch loses 2 minutes in every hour. if the time of the watch is set to 8a.m... (answered by Boreal)

Suppose the life of a particular brand of calculator battery is normally distributed with (answered by ewatrrr)

please help me answer these questions; Do the hypothesis testing to answer this... (answered by rothauserc)

A manufacturer of automobile batteries claims that the average length of life for its... (answered by ewatrrr)

Suppose the life of a particular brand of calculator battery is normally distributed with (answered by ewatrrr)

Assume that the real-world context can be accurately modeled with a linear function.... (answered by stanbon)