Subject: General Aptitude · Chapter: Area · Exam: 2010 · Marks: · Difficulty:
The circumference of a circle is equal to the side of a square whose area measures 407044 sq. cm. What is the area of the circle?
(a)22583.2 sq. cm
(b)32378.5 sq. cm
(c)39483.4 sq. cm
(d)41263.5 sq. cm
(e)Cannot be determined
Answer
Answer (as printed): B
Explanation
Area of the square $=407044 \mathrm{cm}^{2}$. Side of the square $=\sqrt{407044} \mathrm{cm}=638 \mathrm{cm}$. Circumference of circle $=638 \mathrm{cm}$. Let the radius of the circle be $R$ cm. Then, $2 \pi R=638 \Rightarrow R=\frac{638 \times 7}{2 \times 22}=101.5 \mathrm{cm}$. ∴ Area of the circle $=\left(\frac{22}{7} \times 101.5 \times 101.5\right) \mathrm{cm}^{2}=32378.5 \mathrm{cm}^{2}$.