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 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% and for the other it is 99%. Which is which, and how can you tell?