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

Given,

Dimensions of rectangular sheet of paper = 44 cm × 20 cm

When this sheet of paper is rolled along its length:

So,

Circumference of base thus form = 44 cm

= 2πr = 44

= r = \(\frac{44}{2π}\) = \(\frac{44\times 7}{44}\) = 7 cm

Radius = 7 cm

Height = 20 cm

∴ Total surface area of cylinder = 2πr(h + r) = 2 x \(\frac{22}{7}\) x 7 x 27 = 1188 cm²