Question 326271
The number of times a person blinks was studied for a sample of 35 people. The sample's average was 47 blinks per minute. The population standard deviation is 7.8 blinks per minute. What is the 99% confidence interval for the population average?
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xbar = 47 
ME = inbT(0.995 with df=34)*[7.8/sqrt(35)]
= 2.7284*1.3184 = 3.5972
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99% CI: 47-3.5972 < u < 47+3.5972
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Cheers,
Stan H.
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