Geometry

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?    

A cross section of a sphere would be a circle, right?  The largest circle would be through the center, so ...     

A_{through center}  =  π r²  =  3.1416 • 0.5²  =  3.1416 • 0.25     

                       =  0.7854    

 0.7854 • 0.64  =  0.5027 unit²    

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