The radius and height of a solid cylinder is increases by 2% each. What is the percentage change in its curved surface area?

4.04 % 

C.S.A. of cylinder = 2\(\pi \)rh

2% = \(\frac{1}{50}\)

                     Actual   :     New

Radius:           50       :     51

Height:           50       :     51

C.S.A. :        2\(\pi \)RH    :     2\(\pi \)rh

          :           50²      :      51²  = 2500  :  2601

⇒ C.S.A. increased by = 2601 - 2500 = 101

⇒ Increased percentage = \(\frac{101}{2500}\) × 100 = 4.04%