WAEC - Mathematics (1992 - No. 15)
The curved surface area of a cylindrical tin is 704cm\(^2\). Calculate the height when the radius is 8cm. [Take π = 22/7]
3.5cm
7cm
14cm
28cm
32cm
คำอธิบาย
Curved surface area of a cylindrical tin = \(2\pi rh\)
\(\therefore 2\pi rh = 704cm^2\)
\(2 \times \frac{22}{7} \times 8 \times h = 704\)
\(h = \frac{704 \times 7}{2 \times 22 \times 8}\)
\(h = 14cm\)