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The area of a rectangle is A cm^(2) and ...

The area of a rectangle is A `cm^(2)` and length is l cm. Its perimeter (in cm) is

A

`2l+(A)/(l)`

B

`2l+(2A)/(l)`

C

`2l+2A`

D

`2l+(A)/(2l)`

Text Solution

AI Generated Solution

The correct Answer is:
To find the perimeter of a rectangle given its area and length, we can follow these steps: ### Step 1: Understand the given information We know the area \( A \) of the rectangle and the length \( l \). The area of a rectangle is given by the formula: \[ A = \text{length} \times \text{breadth} \] ### Step 2: Express breadth in terms of area and length From the area formula, we can express the breadth \( b \) as: \[ b = \frac{A}{l} \] ### Step 3: Write the formula for the perimeter The perimeter \( P \) of a rectangle is given by the formula: \[ P = 2 \times (\text{length} + \text{breadth}) = 2(l + b) \] ### Step 4: Substitute the expression for breadth into the perimeter formula Now, we substitute the expression for breadth \( b \) into the perimeter formula: \[ P = 2 \left( l + \frac{A}{l} \right) \] ### Step 5: Simplify the expression Distributing the 2 gives us: \[ P = 2l + 2 \left( \frac{A}{l} \right) \] This can be rewritten as: \[ P = 2l + \frac{2A}{l} \] ### Final Answer Thus, the perimeter of the rectangle is: \[ P = 2l + \frac{2A}{l} \text{ cm} \] ---
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BHARDWAJ ACADEMY-MENSURATION -CHAPTER EXERCISE (Previous Years. Questions)
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  2. If the circumference of a circle is 3 cm, then its area, in cm^(2), is

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  3. The area of a rectangle is A cm^(2) and length is l cm. Its perimeter ...

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  4. A cube has a volume 125cm^(3). Area of its one face is

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  5. A square and a circle have equal perimeters. The ratio of the area of ...

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  6. The circumference of the base of a right circular cylinder is 44 cm an...

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  7. ABCD is a square with AB = (x + 6) cm and BC= (3x) cm. The perimeter (...

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  8. The scale of a map is given as 1:10000. On the map, a forest occupies ...

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  9. 42 cubes each of side 1 cm area glured together to form a solid cubo...

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  10. The area of a trapezium-shaped field is 720m^(2), the distance between...

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  11. The base of an isosceles DeltaABC is 48 cm and its area is 168cm^(2). ...

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  12. The area of a square is (16)/(pi) of the area of a circle. The ratio o...

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  13. Four times the area of the curved surface of a cylinder is equal to 6 ...

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  14. If a, b and c are respectively the number of faces, edges and vertices...

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  15. The base radii of two cylinders are in the ratio 2 : 3 and their heigh...

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  16. The perimeter of a trapezium is 104 cm, the lengths of its non-paralle...

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  17. If each edge of a solid cube is increased by 150%, the percentage incr...

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  18. The internal base of a rectangular box is 15 cm long and 12 (1)/(2) c...

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  19. The perimeter of a trapezium is 58 cm and sum of its non-parallel side...

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  20. The sides of a triangle are 6.5 cm, 10 cm and x cm, where x is a posit...

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