Answer:

length + breadth =1/2 of perimeter =120/2 =60

(l+b)*2 = 120

1 l +1/3* l *2 =120 =2 2/3 l= 120

8/3 l =120

8 l =120*3 =360

then l =360/8 =45 m(length)

b =1/3 of length =45*1/3 =15 m(width)

(45+15)*2 =120 is the perimeter of the rectangular

perimeter of a rectangle = 2(l+b) sq.units

120 = 2 (l+b)

120/2 = (l+b)

60 = (l+b)

sum of its length and breadth = 60 m