The sides of a rectangular field are in the ratio 3 : 4. If the area of the field is 9408 sq. m, the cost of fencing the field @ 25 paise per metre is  Options: A) Rs. 55.50 B) Rs. 67.50 C) Rs. 86.50 D) Rs. 98.00 E) None of these
Solution   Let length = (3x) metres and breadth = (4x) metres.   Then, 3x × 4x = 9408 ⇔ 12x2 = 9408 ⇔ x2 = 784 ⇔ x = 28.   So, length = 84 m and breadth = 112 m.   Perimeter = [2(84 + 112)] m = 392 m.   ∴ Cost of fencing = Rs. (0.25 × 392) = Rs. 98.00. Answer Rs. 98.00
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The sides of a rectangular field are in the ratio 3 : 4. If the area of the field is 9408 sq. m, the cost of fencing the field @ 25 paise per metre is