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Ex 11.3
Ex 11.3, 1 (b) Important
Ex 11.3, 1 (c)
Ex 11.3, 2 (a) Important
Ex 11.3, 2 (b) Important
Ex 11.3, 2 (c)
Ex 11.3, 3
Ex 11.3, 4 Important
Ex 11.3, 5 Important
Ex 11.3, 6
Ex 11.3, 7 Important
Ex 11.3, 8 You are here
Ex 11.3, 9 Important
Ex 11.3, 10 Important
Ex 11.3, 11
Ex 11.3, 12 Important
Ex 11.3, 13 Important
Ex 11.3, 14
Ex 11.3, 15
Ex 11.3, 16 Important
Ex 11.3, 17 Important
Last updated at March 30, 2023 by Teachoo
Ex 11.3, 8 Find the cost of polishing a circular table-top of diameter 1.6 m, if the rate of polishing is Rs 15/m2. (Take π = 3.14) Here, Area to be polished = Area of circular table top Diameter = 1.6 m Radius = r = 𝐷𝑖𝑎𝑚𝑒𝑡𝑒𝑟/2 = 1.6/2 = 16/(2 × 10) = 8/10 m Area of table top = 𝜋r2 = 3.14 × (8/10)^2 = 314/100 × 8/10 × 8/10 = (314 × 64)/10000 = 20096/10000 = 2.0096 m2 Now, Cost of polishing 1 m2 area = Rs 15 Cost of polishing 2.0096 m2 area = Rs 15 × 2.0096 = Rs 15 × 20096/10000 = Rs 3 × 20096/2000 = Rs 3 × 10048/1000 = Rs 30144/1000 = Rs 30.144 = Rs 30.14 (approx.) ∴ It will cost Rs 30.14 (approx.) to polish the table top