WAEC - Mathematics (1989 - No. 21)
Calculate the surface area of a hallow cylinder which is closed at one end, if the base radius is 3.5cm and the height 8cm.[take π = 22/7]
126.5cm2
165cm2
176cm2
214.5cm2
253.5cm2
설명
since it is an open cylinder; r= 3.5cm = 7/2cm
h= 8cm;
S.A = 2πrh + πr 2
= πr(2h + r)
(16 + 3.5); 11 x 19.5 = 214.5cm2
h= 8cm;
S.A = 2πrh + πr 2
= πr(2h + r)
(16 + 3.5); 11 x 19.5 = 214.5cm2