WAEC - Mathematics (2007 - No. 16)
A sector of a circle of radius 14cm containing an angle 60o is folded to form a cone. Calculate the radius of the base of the cone.
\(5\frac{1}{2}cm\)
\(4\frac{2}{3}cm\)
\(3\frac{1}{2}cm\)
\(2\frac{1}{3}cm\)
คำอธิบาย
\(r=\frac{\theta \times l}{360^{\circ }}\\
r=?, \theta =60^{\circ }\), l = radius of the orginal sector of a circle = 14cm
\(r=\frac{60\times 14}{360}=\frac{7}{3}=2\frac{1}{3}cm\)
r=?, \theta =60^{\circ }\), l = radius of the orginal sector of a circle = 14cm
\(r=\frac{60\times 14}{360}=\frac{7}{3}=2\frac{1}{3}cm\)