MATHEMATICS 



37 



FRUSTUM OF CYLINDER 



h = 5 sum of greatest and least heights 



= Trdh+-d 2 +area of elliptic top 



PRISM OR PARALLELOPIPED 



C = Ph 



S = Ph+2A 



For prisms with regular polygons as 

 bases, P length of one side X number of sides. 



To obtain area of base, if it is a polygon, divide it into tri- 

 angles and find sum of partial areas. 



FRUSTUM OF PRISM 



If a section perpendicular to the edges is a 

 triangle, square, parallelogram, or regular poly- 



gon, V 



sum of lengths of edges 



number of edges 



X area of right 



section. 



SPHERE 



= 4.1888r3 



CIRCULAR RING 



D = mean diameter; 

 R = mean radius. 



V = 27r 2 #r2 = 2.4674Dd2 

 WEDGE 



