Question

The length of rec triangle is three times its width it the perimeter is 84 find the length of rectangle

Answer 1

let the width be x
length= 3x
perimeter=2(l+b)
84=2(3x+x)
84=2×4x
84=8x
x=84÷8
x=21/2
x=10.5
breadth=10.5
length=10.5×3
length=31.5

Answer 2

CorrecT QuestioN :

The length of rectangle is three times of its width. If the perimeter is 84 cm , then find the length of the rectangle.

ExplanatioN :

Given :-

• The length of rectangle is three times of its width.
• The perimeter is 84 cm.

To find :-

• The length of the rectangle.

Solution :-

Let the width of the rectangle be x cm.

✪ $\sf{Length\:is\:3\: times\:of\:its\: width.}$✪

$\sf{Length=3x\:cm}$

We know,

Perimeter of rectangle =

2 ( Length+Width)

Perimeter = 2(3x+x) cm

→ Perimeter = 8x cm

According to the question,

$\sf{8x=84}$

$\implies\sf{x=\frac{84}{8}}$

$\implies\sf{x= 10.5}$

Width = 10.5 cm

So, Length = 3 × 10.5 = 31.5 cm.

Therefore, the length of the rectangle is 31.5 cm.

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VERIFICATION :

Length = 31.5 cm

Width = 10.5 cm

Perimeter = 84

→ 2(31.5+10.5)=84

→ 84 = 84 ( Verified )

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