Question

a rectangular sheet of paper is 44 cm *18cm is rolled along its length and a cylinder is formed.find the radius of of cylinder

Answer 1

If the sheet is rolled along its length then the circumference will be equal to the length of the rectangle
 Now solve the equation and then find the radius.
2*(22/7)*r= 44cm (Taking pie to be 22/7)
 r= (44*7)/44 = 7cm
So the radius comes out to be 7cm.
Now the height of the cylinder will be equal to the breadth of the rectangle
So the curved surface area of the cylinder will be
2*(22/7)*7*18= 792cm^2