Question

a cylindrical pillar is 1 m in diameter 4.2 metre in height find the cost of whitewashing the curved surface of the pillar at the rate of rupees 15 per metre square

Answer 1

Answer:

the cost of whitewashing is 197.82 Rs

Step-by-step explanation:

given: diameter= 1m   ∴ radius= 1/2 m

         height= 4.2 m

the curved surface area of the cylindrical pillar = 2$\pi$*r*h

                                                              =2*3.14*1/2*4.2

                                                                 =3.14*4.2

                                                                 =13.18 m²

the cost of whitewashing is 15 Rs per meter

hence,  

           = 13.18*15

            =197.82 Rs