Question

104. A rectangular piece of paper 11 cm * 4 cm is folded without overlapping to make a cylinder of height 4 cm. Find the volume of the cylinder:

a. 38.5 cm

b. 35.6 cm

c. 33.5 cm

d. None​

Answer 1

Answer:

option a is correct

Given a Rectangular piece of paper 11cm×4cm is folded without overlapping to make a cylinder of height 4 cm

The length of the paper becomes the circumference of the base of the cylinder and width becomes height.

Let radius of the cylinder=r and height=h

Circumference of the base of cylinder =2πr=11cm

⇒2×722×r=11

∴r=47cm

 Now h=4cm

Volume of the cylinder (V)=πr2h

=722×47×47×4cm3

=38.5cm3

Answer 2

$\huge\sf\fbox\purple{ ♡ Solution ♡ }$

★ Explanation : -

• Correct answer = [ A ] 38.5 cm •

Given : The dimensions of the rectangular paper is 11cm × 4cm

Height of the cylinder is 4cm

Let's look into the below diagram to understand how a rectangular sheet of paper can be converted in to a cylinder

The length of the paper 'l' becomes the circumference of the base of the cylinder and breadth 'b' becomes height of the cylinder

Let the radius of the base and height of the cylinder be 'r' and 'h' respectively

Circumference of the base of cylinder = Length of the rectangle

=> 2πr = 11

=> 2× 22/7 × r = 11

=> r = 7/4 cm

Height of the cylinder = 4cm (given)

Volume of the cylinder is πr2h

Substituting the values of 'r' and 'h' we get

=> (22 × 7 × 7 × 4) / (7 × 4 × 4)

=> 38.5 cm3