A gardener increases the area of his rectangular garden by increasing its length by 40% and decreasing by 20%. The area of the new garden?

A. No change
B. 8%decrease
C. 16% Decrease
D. 16%increases

Explanation:
let the height be ‘h’ and base = b, then area =(1/2 bh)sq.units
New height =(60 % of h) = (60/100 h) = 3h/5
New base =(140% of b) =(140/100 b) =(76/5)
New area =(1/2 x 7b/5 x 3h/5) Sq.units =(21/50 bh)sq.units
Decrease in area =(1/2bh – 21/50bh)= 4/50 bh
Decrease % =(4/50bh. 2/bh x 100)% =16%