Question

A rectangular sheet of paper, 44 cm × 20 cm, is rolled along its length to form a cylinder. Find the total surface area of the cylinder thus generated.

 

Answer 1

\[\text{ The rectangular sheet of paper 44 cm } \times 20 \text{ cm is rolled along its length to form a cylinder . The height of the cylinder is 20 cm and circumference is 44 cm }  . \]
\[\text{ We have } : \]
\[ \text{ Height, h = 20 cm } \]
\[\text{ Circumference } = 2\pi r = 44 cm\]
\[ \therefore \text{ Total surface area is S }  = 2\pi rh\]
\[ = 44 \times 20 \text{ cm } ^2 \]
\[ = 880 \text{ cm } ^2 \]