Question

A rectangular paper of dimensions 8 cm by 5 cm is rolled to form a cylinder of height equal to width of the paper find the radius of the cylinder so rolled​

Answer 1

Answer:

Area of the rectangle = 40cm ^ 2

so,the area of the rectangle will be equal to the area of the cylinder.

40cm^2 = 2 π rh

= 40= 2 ×π× r × 5

since it is folded height will be the breadth of the rectangle.

= 40= 10π

= 4π cm ( Ans)