8. From a solid cylinder whose height is 2.4 cm and diameter 1.4 cm, a conical cavity of the same height and same diameter is hollowed out. Find the total surface area of the remaining solid to the nearest .
Height of Cylinder =h =AO=2.4 cm
Diameter of Cylinder = 1.4 cm
Radius of Cylinder = Radius of Cone = OB = r cm
Using Pythagoras Theorem on to find Slant Height () of cone, we get
Surface Area of remaining Solid = Surface Area of Cylinder Part + Inner surface Area of Hollow Cone
Total surface area of the remaining solid to the nearest =18