Biology and Environmental Science Koalas are not really bears, but are related to the wombat and the kangaroo and live in eastern Australia. These cuddly-looking creatures grow to a size of 23.5 to 33.5 inches and are a threatened species.
A random sample of 35 koalas was obtained, and each was carefully weighed. The mean weight was = 20.75 pounds. Assume σ = 3.05 pounds.
a. Find a 99% confidence interval for the mean weight of all koalas.
b. Researchers believe that if the true mean weight is less than 23 pounds, these animals may be suffering from malnutrition. Is there any evidence to suggest that the koala population is suffering from malnutrition? Justify your answer.