Perform a Test for Independence
-A Medical Researcher Is Interested $\alpha = 0.01$

question 18

Short Answer

Perform a Test for Independence
-A medical researcher is interested in determining if there is a relationship between adults over 50 who exercise regularly and low, moderate, and high blood pressure. A random sample of 236 adults over 50 is selected and the results are given below. Test the claim that regular exercise and low, moderate, and high blood pressure are independent. Use $\alpha = 0.01$ .
$\begin{array}{l|ccc}\text { Blood Pressure } & \text { Low } & \text { Moderate } & \text { High } \\\hline \text { Reg. Exercise } & 35 & 62 & 25 \\\text { No Reg. Exercise } & 21 & 65 & 28\end{array}$

---

Definitions:

Elasticity

The ability of a material or body to resume its normal shape after being stretched or compressed.

Parabronchi

Minute tubular air passages within the lungs of birds through which respiratory gas exchange occurs, part of their highly efficient respiratory system.

Birds

Warm-blooded vertebrates characterized by feathers, beaks without teeth, and laying hard-shelled eggs.

Countercurrent Exchange

A mechanism in which fluids flow in opposite directions, exchanging properties (such as heat or chemical constituents) to maximize transfer rates.