Question

17. The length and breadth of a rectangle are in the ratio 3 : 2. If its area is 216 cm², then its perimeter is
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Answer 1

Let the common multiple be x.

Area= length × breadth

$216 = (3x)(2x)$

$216 = 6 {x}^{2}$

${x}^{2} = \frac{216}{6}$

${x}^{2} = 36$

$x = \sqrt{36}$

$x = 6$

Length=3×6

=18cm

Breadth=2×6

=12cm

Perimeter=2(length+breadth)

=2(18+12)

=2×30

=60cm

Perimeter is 60cm.