Question

the area of four walls of a room is 660 metre square and its length is twice its breadth if the height of the room is 11metre then the area of the floor in metre square is​

Answer 1

Answer:

Step-by-step explanation:

Given,

Area of four walls = 660 m²

Height = 11 m

And its length is twice its breadth.

To Find,

Area of the floor,

Formula to be used,

Area of four walls = 2(l + b) × h

Area of floor = l × b

Solution,

Let the width be b m  and the length be 2b m.

Them,

Area of four walls = 2(l + b) × h

⇒ 660 = 2 (2b + b) × 11

⇒ 660 = 2 (3b) × 11

⇒ 660/11 = 6b

⇒ 60 = 6b

⇒ b = 60/6

⇒ b = 10 m

Here, the breadth is 10 m

Length = 2 × Breadth

⇒ Length = 2 × 10

⇒ Length = 20 m

Here, the length is 20 m

Now, the area of the floor,

Area of floor = l × b

⇒ Area of floor = 20 × 10

⇒ Area of floor = 200 m².

Hence, the Area of thefloor is 200 m².

Answer 2

$\Large{\bold{\blue{\underline{GiVeN\::}}}}$

• The area of four walls of a room is 660 m².

• The length is twice it's breadth.

$\bf\red{Let,}$

$\longmapsto\:\:\bf{Breadth\:(b) \:is \:x\:m}.$

$\bf\pink{So,}$

$\longmapsto\:\:\bf{Length\:(l) \:is \:2x\:m}.$

• The height of the room is 11 m.

$\longmapsto\:\:\bf{Height \:(h)\:=\:11\:m}$

$\Large{\bold{\purple{\underline{To\:FiNd\::}}}}$

• The area of the floor.

$\Large{\bold{\pink{\underline{CaLcUlAtIoN\::}}}}$

$\bf\orange{According\:to\:the\:question,}$

$\red\checkmark\:\:\bf{Area\:of\:4\:walls\:=\:660\:m^2}$

$:\implies\:\:\bf{2\:(l\:+\:b)\times{h}\:=\:660}$

$:\implies\:\:\bf{2\:(2x\:+\:x)\times{11}\:=\:660}$

$:\implies\:\:\bf{2\times{3x}\times{11}\:=\:660}$

$:\implies\:\:\bf{66x\:=\:660}$

$:\implies\:\:\bf{x\:=\:\dfrac{660}{66}}$

$:\implies\:\:\bf\blue{x\:=\:10}$

$\Large\bf\green{Hence,}$

➣ Breadth is 10 m.

$\bf\red{And,}$

$\longmapsto\:\:\bf{Length\:(l) \:= \:2\times{10}}$

$\longmapsto\:\:\bf{Length\:(l) \:= \:20\:m}$

$\Large\bf\purple{Hence,}$

➣ Length is 20 m.

$\\ \Large\bf\pink{Now,}$

$\orange\checkmark\:\:\bf{Area\:of\:floor\:=\:l\times{b}}$

$:\implies\:\:\bf{Area\:of\:floor\:=\:20\times{10}}$

$:\implies\:\:\bf\blue{Area\:of\:floor\:=\:200\:m^2}$

━─━─━─━─━─━─━─━─━─━─━─━─━─━─━

$\Large\bf\orange{Therefore,}$

The area of the floor is 200 m²