Question

Shell lengths of sea turtles. Refer to the Aquatic Biology (Vol. 9, 2010) study of green sea turtles inhabiting the Grand Cayman South Sound lagoon, Exercise 2.83 (p. 65). Research shows that the curved carapace (shell) lengths of these turtles has a distribution with mean μ = 50 cm and standard deviation σ = 10 cm. In the study, n = 76 green sea turtles were captured from the lagoon; the mean shell length for the sample was = 55.5 cm. How likely is it to observe a sample mean of 55.5 cm or larger?