Helium balloon

Oscar needs to fill a sphere-shaped balloon with helium. If the balloon has a diameter of 8 inches, what is the total amount of helium that the balloon will hold to the nearest tenth?

Correct answer:

V =  268.1 in³

Step-by-step explanation:

$$\begin{gathered} d=8\text{in} \\ r=d/2=8/2=4\text{in} \\ V=\frac{4}{3}\cdot \pi \cdot r^3=\frac{4}{3}\cdot 3.1416\cdot 4^3=268.1{\text{in}}^3 \end{gathered}$$

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