Question

2. Medical researchers have developed a new artificial heart constructed primarily of titanium and plastic. The heart will last and operate almost indefinitely once it isimplemented in the patient’s body, but the battery pack needs to be recharged about every six hours. A random sample of 40 battery packs is selected and subjected to a life test. The average life of these batteries is 6.05 hours. Assume that battery life isnormally distributed with standard deviation 0.2 hours. Use α=0.05.

   (a) Compute the power of the test if the true mean batter life is 6.1 hours. (b) If we want β=0.10 at μ=5.9, what sample size should we use?

Answer 1