The two intervals (114.4, 115.6) and (114.1, 115.9) are confidence intervals (computed using the same sample data) for μ = true average resonance freq

ruigE 2021-05-09 Answered

The two intervals (114.4, 115.6) and (114.1, 115.9) are confidence intervals (computed using the same sample data) for \(\mu=\) true average resonance frequency (in hertz) for all tennis rackets of a certain type.
a. What is the value of the sample mean resonance frequency?
b. The confidence level for one of these intervals is 90%90%and for the other it is 99%99%. Which is which, and how can you tell?

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curwyrm
Answered 2021-05-10 Author has 25386 answers

To conclude,
(a) The sample mean resonance frequency is 115.
(b) The confidence level of \(\displaystyle{I}_{{{1}}}\)\(=(114.4,115.6)\) is 90% and confidence level of \(\displaystyle{I}_{{{2}}}\)\(=(114.1,115.9)\) is 99%

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