Question

a rectangular peice of paper 11cm×4cm is folded without overlapping to make a cylinder of height 4cm. the volume of the cylinder so formed is
(a)9.6cm
(b)22.5cm
(c)38.5cm
(d)154cm

Answer 1

Circumference of the cylinder = Length of the rectangle

2πr = 11 cm
r = 11 * 7/22 * 1/2
r = 7/4  (or) 1.75 cm

Volume of the cylinder = πr²h = 22/7 * 1.75 * 1.75 * 4
 
                                    = 22/7 * 7/4 * 7/4 * 4

                                   =  38.5 cm³