Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
The perimeter of a circle is equal to the perimeter of a square. Then, their areas are in the ratio
(a)4 : 1
(b)11 : 7
(c)14 : 11
(d)22 : 7
Answer
Answer (as printed): C
Explanation
Let the radius of the given circle be $R$ cm and the side of the square be $a$ cm. $$\text { Then, } 2 \pi R=4 a \Leftrightarrow \frac{R}{a}=\frac{2}{\pi} \text {. } \begin{aligned} \text { Ratio of their areas } & =\frac{\pi R^{2}}{a^{2}} \\ & =\left(\pi \times \frac{4}{\pi^{2}}\right)=\left(\frac{4}{22} \times 7\right) \\ & =\frac{14}{11}=14: 11 . \end{aligned}$$
Explanation as extracted from the printed page; notation may be imperfect.