If the length of a rectangle is increased by 20% and breadth decreased by 15%, then area will be:

2% increase

If length = l, breadth = b and  Area = lb

Then,

ATQ,

New length = $\frac{6}{5}$ × l, New breadth = $\frac{17}{20 }$b

Now, New Area = $\frac{6}{5}$l × $\frac{17}{20}$b

                                = $\frac{102}{100}$lb

∴ Area increases by 2%