Question

the perimeter of the floor of a room is 18metre and its height is 3 metre find the area of four walls of a room​

Answer 1

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If the floor is in rectangular shape

Then your answer is,

Perimeter of rectangle =2(l+b)

18=2(l+b)

Then,

$Area \: of \: four \: walls =2(l+b) \times h$

$Area \: of \: four \: walls=18 \times 3$

$Area \: of \: four \: walls =54m²$