The perimeter of a rectangle is 14 8 15 cm . If its length is 4 2 3 cm , find its area.

Given length of a rectangle l = 4 2 3 cm Let the breadth of the rectangle is b cm . We know that perimeter of the rectangle is 2 l + b Given perimeter of the rectangle is 14 8 15 cm . ⇒ 2 l + b = 14 8 15 ⇒ 2 4 2 3 + b = 14 8 15 ⇒ 2 4 × 3 + 2 3 + b = 14 × 15 + 8 15 ⇒ 2 12 + 2 3 + b = 210 + 8 15 ⇒ 2 14 3 + b = 218 15 ⇒ 14 3 + b = 218 5 × 1 2 ⇒ b = 218 30 - 14 3 ⇒ b = 218 - 140 30 ⇒ b = 78 30 ⇒ b = 13 5 = 2 3 5 cm We know that area of the rectangle is l × b . ⇒ 4 2 3 × 13 5 ⇒ 4 × 3 + 2 3 × 13 5 ⇒ 14 3 × 13 5 ⇒ 182 15 cm 2 = 12 2 15 cm 2 Hence, the area of the rectangle is 12 2 15 cm 2

HARD

Earn 100

In the rectangular plot of land:

A: Plot of land.

B: Wet land.

Find the area of B when area of A $= 200 sq . m$ .

Important Questions on Area and its Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

In the following figure, $seg DH ⊥ seg EF$ and $seg GK ⊥ seg EF$ . If $DH = 6 cm, GK = 10 cm$ and $A (△ DEF) = 150 {cm}^{2}$ , then find $EF$ in $cm$ .

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

A wire encloses an area of

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From a rectangular piece of metal sheet of length and breadth

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

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Mathematics>Geometry>Area and its Boundary>Area and Boundary

A wire is bent to form a square of area $169 \mathrm{~cm}^{2}$. If the same wire is bent to form a circle, then what is its area (in $\mathrm{cm}^{2}$, to the nearest whole number)?
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Mathematics>Geometry>Area and its Boundary>Area and Boundary

What is the area of the largest square which can be inscribed in a circle of radius