The triangular side walls of a flyover have been used for advertisements. The sides of the walls are 13 m, 14 m and 15 m. The advertisements yield and earning of Rs. 2000 per m2 a year. A company hired one of its walls for 6 months. How much rent did it pay?


a = 13, b = 14, c = 15

s = (a + b + c)/2


s = (13 + 14 + 15)/2 = 42/2 = 21.


Area(Δ) = √s(s-a)(s-b)(s-c)


Area(Δ) = √21(21-13)(21-14)(21-15)


Area(Δ) = √21×8×7×6


Area(Δ) = 84m2


Cost of advertisements for a year = Area(Δ) × Cost per m2


Cost of advertisements for a year = 84×2000 = Rs. 168000


As the company only rented the board for 6 months:


Cost of advertisements for 6 months =


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