A 160° sector of a circle radius 10.5cm is bent to form a cone.Find the area of the base of the cone, correct to the nearest cm.
AAAaannndd the bot gets it wrong yet again!
the radius of the base is 10.5 * 160/360 = 14/3 cm
so the area is π(14/3)^2 = 196π/9 = 68.4 cm^2
using the area of the original sector is just wrong - that gives the lateral area of the cone.
The area of the base of the cone is equal to the area of the sector of the circle.
Area of sector = (1/2)r^2θ
Area of base = (1/2) x (10.5 cm)^2 x (160°/360°)
Area of base = 88.5 cm^2
Area of base (correct to nearest cm) = 89 cm^2