The manufacturer of a particular battery pack for laptop computers claims its battery pack can function for 8 hours, on the average, before having to be recharged. A random sample of 16 battery packs was selected and tested. The mean functioning time before having to be recharged was 7.2 hours with a standard deviation of 1.9 hours.
Assuming the distribution of functioning times is approximately normal, find a 95% confidence interval for the true average functioning time before needing to be recharged. Interpret the interval in part (a). Based on the interval in part (a), can the manufacturer's claim be rejected? Justify your answer.
a. What is the 95% confidence interval (CI)?
CI = ______________ Enter (n1, n2)
Interpret the interval:
________________________________________________________
The claim ______________ be rejected.
Justify your answer

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The Answer of The manufacturer of a particular battery pack for laptop computers claims its battery pack can function for 8 hours, on the average, before having to be recharged. A random sample of 16 battery packs was selected and tested. The mean functioning time before having to be recharged was 7.2 hours with a standard deviation of 1.9 hours.
Assuming the distribution of functioning times is approximately normal, find a 95% confidence interval for the true average functioning time before needing to be recharged. Interpret the interval in part (a). Based on the interval in part (a), can the manufacturer's claim be rejected? Justify your answer.
a. What is the 95% confidence interval (CI)?
CI = ______________ Enter (n1, n2)
Interpret the interval:
________________________________________________________
The claim ______________ be rejected.
Justify your answer

The Manufacturer of a Particular Battery Pack for Laptop Computers