document.write( "Question 1210141: The area of a cross section of a sphere is 64\% of the largest possible cross sectional area of the sphere. If the sphere has radius 1/2, what is the area of the cross section?
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Algebra.Com's Answer #851363 by CPhill(1959)![]() ![]() You can put this solution on YOUR website! Let the sphere have radius $r$. \n" ); document.write( "The largest possible cross-sectional area of the sphere is a circle with radius $r$, so its area is $\pi r^2$. \n" ); document.write( "Given that the radius of the sphere is $r = \frac{1}{2}$, the largest possible cross-sectional area is $\pi (\frac{1}{2})^2 = \frac{\pi}{4}$.\r \n" ); document.write( "\n" ); document.write( "The area of the cross section is 64\% of the largest possible cross-sectional area. \n" ); document.write( "Therefore, the area of the cross section is $0.64 \cdot \frac{\pi}{4}$. \n" ); document.write( "$$ 0.64 \cdot \frac{\pi}{4} = \frac{64}{100} \cdot \frac{\pi}{4} = \frac{16}{25} \cdot \frac{\pi}{4} = \frac{4\pi}{25} $$\r \n" ); document.write( "\n" ); document.write( "Thus, the area of the cross section is $\frac{4\pi}{25}$.\r \n" ); document.write( "\n" ); document.write( "Final Answer: The final answer is $\boxed{\frac{4 \pi}{25}}$ \n" ); document.write( " \n" ); document.write( " |