Subject: General Aptitude · Chapter: Area · Exam: 2006 · Marks: · Difficulty:
Of the two square fields, the area of one is 1 hectare while the other one is broader by 1\%. The difference in their areas is
(a)$100 \mathrm{m}^{2}$
(b)$101 \mathrm{m}^{2}$
(c)$200 \mathrm{m}^{2}$
(d)$201 \mathrm{m}^{2}$
Answer
Answer (as printed): D
Explanation
Area $=1$ hect. $=10000$ sq. m. $\Rightarrow$ side $=\sqrt{10000} \mathrm{m}=100 \mathrm{m}$. Side of the other square = 101 m. Difference in their areas $=\left[(101)^{2}-(100)^{2}\right] \mathrm{m}^{2}$ $$\begin{aligned} & =[(101+100)(101-100)] \mathrm{m}^{2} \\ & =201 \mathrm{m}^{2} \end{aligned}$$