Mathematics for IGCSE & O level - Mensuration (Section 2 - No. 26)
A cone has slant height 8cm and curved surface area 63 cm². Calculate the total surface area of the cone.
70.3 cm²
88.5 cm²
94.2 cm²
108.6 cm²
Forklaring
Curved surface area = πrl=63cm². r = 63/πl= 2.5, Therefore total surface area of cone = 63 +πr²=82.5 cm²