Subject: General Aptitude · Chapter: Area · Exam: 2010 · Marks: · Difficulty:
Cost of fencing a circular plot at the rate of ₹ 15 per metre is ₹ 3300. What will be the cost of flooring the plot at the rate of ₹ 100 per square metre?
(a)₹ 2,20,000
(b)₹ 3,50,000
(c)₹ 3,85,000
(d)Cannot be determined
(e)None of these
Answer
Answer (as printed): C
Explanation
Circumference of the plot $=\left(\frac{3300}{15}\right) \mathrm{m}=220 \mathrm{m} . \quad 2 \pi R=220$ $$\Rightarrow R=\frac{220 \times 7}{2 \times 22}=35 \mathrm{m} .$$ Area of the plot $=\left(\frac{22}{7} \times 35 \times 35\right) \mathrm{m}^{2}=3850 \mathrm{m}^{2}$. $$\text { ∴ Cost of flooring }=₹(3850 \times 100)=₹ 385000 \text {. }$$