Question

If the side of a square is increased by 30%, its area is increased by

• A. 49%
• B. 69%
• C. 79%
• D. None of these

Answer 1

The correct option is B 69%

$Sinceside\times side=area$
$\therefore$ Net % change in area

$=(x+y+\frac{xy}{100})\%$

$=(30+30+\frac{30\times 30}{100})\%$
= 69%.
$\therefore$ The area is increased by 69%.