Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
There are 4 semi-circular gardens on each side of a square-shaped pond with each side 21 m. The cost of fencing the entire plot at the rate of ₹ 12.50 per metre is
(a)₹ 1560
(b)₹ 1650
(c)₹ 3120
(d)₹ 3300
Answer
Answer (as printed): B
Explanation
Length of the fence $=4 \pi \mathrm{R}$, where $R=\frac{21}{2} m$ $$=\left(4 \times \frac{22}{7} \times \frac{21}{2}\right) \mathrm{m}=132 \mathrm{m} .$$ Cost of fencing $=₹\left(132 \times \frac{25}{2}\right)=₹ 1650$.