# The perimeter of a square is 240 cm.The ratio of length is to breadth is 7:5 .Write the area

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by Petunia

its a rectangle or a square

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by Petunia

its a rectangle or a square

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let us take x as a constant

then,

length=7x

breadth=5x

perimeter of rectangle=240cm

2(l+b)=240

2(7x+5x)=240

24x=240

x=240/24

x=10cm

by substituting x=10cm in length and breadth

length=70cm

breadth=50cm

area of rectangle=length×breadth

=70×50

area of rectangle=3500cm²

The Brainliest Answer!

Ratio of length is to breadth = 7 : 5

The semi-perimeter of the rectangle = 240 / 2

= 120

Total number of parts in ratio = 7+5 = 12

Each part = 120 / 12 = 10

.'. The length of rectangle = 7 parts of 120

= 10 * 7

= 70 cm

.'.The breadth of rectangle = 5 parts of 120

= 10 * 5

= 50 cm

.'.Area of the rectangle = length* breadth

= 50 * 70

= 3500 square cm

.'. Answer = 3500 square cm