Let initial dimensions be, l & b ∴ Final length is 1.4 l Final breadth is 0.8 b ∴ Final area is = 1.4 l × 0.8 b = 1.12 lb ∴ Area is increased by 12%. Shortcut Method: +40−20+
40×(−20)
100
=20−8=12% Therefore, the area of the new garden increased by 12%