Diagnostic Tests: Total Calcium Over the past several months, an adult patient has been treated for tetany (severe muscle spasms). This condition is associated with an average total calcium level below 6 mg/dl (Reference:

Manual of Laboratory and Diagnostic Tests by F. Fischbach). Recently, the patient’s total calcium tests gave the following readings (in mg/dl).

9.3 8.8 10.1 8.9 9.4 9.8 10.0 9.9 11.2 12.1

(a) Use a calculator to verify that x 5 9.95 and s < 1.02.

(b) Find a 99.9% confi dence interval for the population mean of total calcium in this patient’s blood.

(c) Interpretation Based on your results in part (b), does it seem that this patient still has a calcium defi ciency? Explain.