A painter needs to cover a triangular region 64 meters by 68

A painter needs to cover a triangular region 64 meters by 68 meters by 72 meters. A can of paint covers 70 square meters. How many cans will be needed?

Solution

Number of cans needed=area of triangular region/ area covered by can

Area of triangle= sqrt(s(s-a)(s-b)(s-c))

s=(a+b+c)/2

s= (64+68+72)/2= 102

area=sqrt(102(102-64)(102-68)(102-72))=sqrt(102*38*34*30) = sqrt(3953520)= 1988.35

Number of can=1988.35/70=28.4