Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
Four equal circles are described at the four corners of a square so that each touches two of the others. The area enclosed by the circumferences of the circles is $13 \frac{5}{7}$ sq. cm. Find the radius of the circle.
(a)2.5 cm
(b)4 cm
(c)6 cm
(d)7.5 cm
Answer
Answer (as printed): B
Explanation
As discussed in Q. 379, we have : $$\frac{6 a^{2}}{7}=\frac{96}{7} \Rightarrow a^{2}=\frac{96}{7} \times \frac{7}{6}=16 \Rightarrow a=4 \mathrm{cm} .$$