The perimeter of a triangular field is 144 m and the ratio of the sides is 3 : 4 : 5. Find the area of the field.
Sides of triangle are in ratio: 3 : 4 : 5
Since the perimeter of a triangle is given by:
Therefore sides of the triangle are:
When a, b and c are the sides of triangle and s is the semi-perimeter, then its area is given by:
A = 
where 
[Heron’s Formula]
= 
= 72
A = 
A = 
= 
cm2
6