Question

The triangular side walls of a flyover have been used for advertisements. The sides of the walls are $122m,22m$ and $120m$ (see figure). The advertisements yield an earning of $Rs.5000per{m}^2$ per year. A company hired one of its walls for $3$ months. How much rent did it pay?

Answer 1

Given:

$\Rightarrow$Sides: $a=122m$, $b=22m$ and $c=120m$

$\Rightarrow$Perimeter, $P=122+22+120=264m$

$\Rightarrow$Semi perimeter $=S=\frac{264}{2}$, $S=132m$

$\Rightarrow$$A=\sqrt{s(s-a)(s-b)(s-c)}$ ........(Heron's formula)

$\Rightarrow$$A=\sqrt{132(132-122)(132-22)(132-120)}$

$\Rightarrow$$=\sqrt{132\times 110\times 10\times 12}=1320m^2$

$\Rightarrow$For $1m^2$, area per year, rent $=Rs.5000$

$\Rightarrow$For $1m^2$, area per month rent $=\frac{Rs.5000}{12}$

$\Rightarrow$For $1320m^2$, area 3 months rent $=\frac{Rs.5000}{12}\times 3\times 1320$

$\Rightarrow$Rent $=Rs.1650000$