Subject: General Aptitude · Chapter: Area · Exam: 2007 · Marks: · Difficulty:
A circular grassy plot of land, 42 m in diameter, has a path 3.5 m wide running around it outside. The cost of gravelling the path at ₹ 4 per square metre is
(a)` 1002
(b)` 1802
(c)` 2002
(d)` 3002
Answer
Answer (as printed): C
Explanation
Radius of the plot = 21 m. Area of the path = p[(24.5)2 – (21)2] m2 = [p(24.5 + 21) (24.5 – 21)] m2 22 2 2 = × 45.5 × 3.5 m = 500.5 m . 7 \ Cost of gravelling = ` (500.5 × 4) = ` 2002. 22 3 2 2
Explanation as extracted from the printed page; notation may be imperfect.