Solution:
(i) Perimeter of the rectangular field = 240 m
2(l + b) = 240 m
= > l + b = 120 m
=> 90 m + b = 120 m
= > b = 120 m – 90 m = 30 m
So, the breadth = 30 m.
(ii) Area of the rectangular field = l × b
= 90 m × 30 m
= 2700 m2
So, the required area = 2700 m2