Question

A rectangular sheet of paper is folded about its width 15cm . If the length of the sheet is 22m find the volume of the hollow cylinder thus formed

Answer 1

Height of cylinder = Width of rectangle.

Height = 15 cm

Circumference of Base of cylinder = Length of rectangle..

=> 2 pi r = 22

=> 2*22*r/7 = 22

=> r = 22*7 / 22*2

=> r = 3.5 cm


Volume = pi *r^2 h

= 22*3.5*3.5*15 / 7

= 22*0.5*3.5*15

= 11*15*3.5

= 577.5 cm^3

Answer 2

Hi,

Here is your answer,
                                                     { Height and width }

h =15 cm                                           { Circumference of base of hollow 
                                                            cylinder = length of rectangular sheet }
→ 2πr = 22

→2 × 22 × /7 = 22

→r = 22 × 7/ 22 × 2 → 154/44 = 3.5

So, radius = 3.5 cm

Volume(V) = π×r²h 

→22 × 3.5 × 3.5 × 15 / 7            { Taking 3.5 common}

→ 22 × 0.5 × 3.5 × 15

→11 × 15 × 3.5

→577.5 cm³


Hope it helps you !