02:08
Intermediate Algebra for College Students
Your cardiac index is your heart's output, in liters of blood per minute, divided by your body's surface area, in square meters.
The cardiac index, $C(x),$ can be modeled by
\[C(x)=\frac{7.644}{\sqrt[4]{x}}, \quad 10 \leq x \leq 80\]
where $x$ is an individual's age, in years. The graph of the function is shown. Use the function to solve.
a. Find the cardiac index of a 32 -year-old. Express the denominator in simplified radical form and reduce the fraction.
b. Use the form of the answer in part (a) and a calculator to express the cardiac index to the nearest hundredth. Identify your solution as a point on the graph.