Question

A wooden bookshelf has external diamensions as follows -Height-110cm,Depth-25cm,Breadth-85cm.The thickness of the planks is 5cm everywhere. the external faces are to be polished and the inner faces are to be painted. if the rate of polishing is 20 paise per square cm and the rate of painting is 10 paise per square cm. A. External surface area will be (1)12100cm^2 (2)8500cm^2 (3)32100cm^2 (4)19100cm^2 B. internal surface area will be- (1)14500cm^2 (2)2900cm^2 (3)16000cm^2 (4)1500cm^2 C.Total expenses will be- (1)rs5240 (2)rs4810 (3)rs2940 (4)rs1710 D.difference of cost of painting to cost of polishing is- (1)rs1105 (2)rs990 (3)rs4520 (4)rs720 E.Ratio of external surface area to internal surface area is (1)145:191 (2)290:105 (3)23:25 (4)11:17​

Answer 1

Answer:

A wooden bookshelf has external diamensions as follows -Height-110cm,Depth-25cm,Breadth-85cm.The thickness of the planks is 5cm everywhere. the external faces are to be polished and the inner faces are to be painted. if the rate of polishing is 20 paise per square cm and the rate of painting is 10 paise per square cm. A. External surface area will be (1)12100cm^2 (2)8500cm^2 (3)32100cm^2 (4)19100cm^2 B. internal surface area will be- (1)14500cm^2 (2)2900cm^2 (3)16000cm^2 (4)1500cm^2 C.Total expenses will be- (1)rs5240 (2)rs4810 (3)rs2940 (4)rs1710 D.difference of cost of painting to cost of polishing is- (1)rs1105 (2)rs990 (3)rs4520 (4)rs720 E.Ratio of external surface area to internal surface area is (1)145:191 (2)290:105 (3)23:25 (4)11:17