Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
What is the area of the circle ? (Bank P.O., 2009) I. Perimeter of the circle is 88 cm. ONS) II. Diameter of the circle is equal to the side of the square having area 784 sq. cm.
Answer
SELF-PRACTICE — the source book printed no answer.
Nothing is invented here, so this question has no answer on record.
Explanation
Let the radius of the circle be $r$. I. Perimeter $=2 \pi r=88 \Rightarrow r=\left(\frac{88 \times 7}{2 \times 22}\right)=14 \mathrm{cm}$. ∴ Area $=\pi r^{2}=\left(\frac{22}{7} \times 14 \times 14\right) \mathrm{cm}^{2}=616 \mathrm{cm}^{2}$. II. $2 r=$ Side of the square $=\sqrt{784} \mathrm{cm}=28 \mathrm{cm} \Rightarrow r=14 \mathrm{cm}$. ∴ Area $=\pi r^{2}=\left(\frac{22}{7} \times 14 \times 14\right) \mathrm{cm}^{2}=616 \mathrm{cm}^{2}$.