Question

A solid cylinder has total surface area of 462 cm square . It's CSA is one third of the TSA

Answer 1

Given:

           Total surface area of a cylinder is 462 cm^2

           2πr^2 + 2πrh = 462 cm^2 ...........eq.1

           And also;

                          CSA = 1/3(TSA).   =>    2πrh = 2/3(πr(r+h))

                          => h = 1/3(r+h)

                          => 3h-h = r

                          2h = r............eq.2

         From eq.1 and eq.2;

                  2πr^2 + πr^2 = 3πr^2 = 462 => r^2 = 49 => r = 7

       

       R = 7 ; h = 14