Question

10. The length and width of a rectangle are in the ratio 5:3. Find the dimensions of the rectangle, if its perimeter
is 112 cm. ​

Answer 1

$\sf{\huge{\underline{\pink{Given :-}}}}$

• The length and width of a rectangle are in the ratio 5:3.

• The perimeter of rectangle is 112 cm.

$\sf{\huge{\underline{\blue{To\:Find :-}}}}$

• The dimensions of the rectangle.

$\sf{\huge{\underline{\purple{Solution :-}}}}$

Let the dimesion be x,

So, The length of a rectangle :- 5x

The width of a rectangle :- 3x

We know , the perimeter of a rectangle is 2 (l + b)

We have, The perimeter of rectangle is 112 cm.

➝ 2 (l + b) = 112

➝ 2 ( 5x + 3x ) = 112

➝ 2 × 8x = 112

➝ 16x = 112

➝ x = $\cancel{\dfrac{112}{16}}$

➝ x = 7 cm

We get,

The length of a rectangle :- 5x = 5×7 = 35 cm

The width of a rectangle :- 3x , 3×7 = 21 cm

Hence, The dimensions of the rectangle (35 × 21).

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