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MATHEMATICS 

 CONE 



FRUSTUM OF CONE 



SPHERE 



? = vd 2 = 4irr2 = 12.5664r 2 

 Td 3 = $irr 3 = .5236^ = 4. 1888r 



CIRCULAR RING 



Z) = mean diameter; 

 R = mean radius. 



PRISMOID 



A prismoid is a solid having two parallel plane ends, the 

 edges of which are connected by plane triangular or quadri- 

 lateral surfaces. A = area of one end ; 

 a = area of other end; 



area of section midway between ends; 

 perpendicular distance between ends. 



The area m is not in general a mean between the areas of 

 the two ends, but its sides are means between the corresponding 

 lengths of the ends. 



