CMA Foundation · Fundamentals of Business Mathematics and Statistics · Quadratic Equations
A rectangular plot owned by Mr. Iyer has length 3 metres more than its breadth. Its area is 270 square metres. What is its perimeter?
The perimeter is 66 metres. Setting b(b+3)=270 gives b=15 metres and length 18 metres after rejecting the negative root. Twice the sum of the sides, 2 times 33, gives 66 metres.
- A66 metresCorrect
- B33 metres
- C60 metres
- D72 metres
Explanation
Let breadth be b: b(b+3)=270, so b^2+3b-270=0, (b+18)(b-15)=0, b=15 (reject negative). Length = 18. Check 15x18=270. Perimeter = 2(15+18)=66 m. Option 33 is only the semi-perimeter.
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