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

**Solution:**

Length of first side of triangle **m**

Length of second side of triangle **m**

Length of third side of triangle **m**

Semi-perimeter of triangle **m**

Using** Heron's formula** to find area of triangle, we get

Area of triangle

1 of area costs Rs 5000 in advertising for 12 months

So, cost of 1320 of area for 12 months **Rs**

Cost of 1320 of area for 3 months **Rs**