Question

The ratio of length and breadth of a rectangle is 3:1 & its perimeter is
36cm. Find length & breadth of rectangle
*

​

Answer 1

• Length of rectangle is 13.5 cm.
• Breadth of rectangle is 4.5 cm.

Step-by-step explanation:

Given:-

• Ratio of Length and breadth of rectangle is 3:1.
• Perimeter of rectangle is 36 cm.

To find:-

• Length and Breadth of rectangle.

Solution:-

Let, Length of rectangle be 3x.

And Breadth of rectangle be x or 1x.

We know that,

Perimeter of rectangle = 2(Length + Breadth)

Put Length, Breadth and Perimeter of rectangle in formula

$\longrightarrow$ 2(Length + breadth) = 36

$\longrightarrow$ 2(3x + x) = 36

$\longrightarrow$ 6x + 2x = 36

$\longrightarrow$ 8x = 36

$\longrightarrow$ x = 36/8

$\longrightarrow \purple{ \boxed{\sf \bold{x = 4.5}}\star}$

Verification:-

$\longrightarrow$ 2(3x + x) = 36

• Put x = 4.5

$\longrightarrow$ 2(3×4.5 + 4.5) = 36

$\longrightarrow$ 2×(13.5 + 4.5) = 36

$\longrightarrow$ 27 + 9 = 36

$\longrightarrow$ 36 = 36

Hence Verified!!

Now,

Length of rectangle = 3x = 3×4.5 = 13.5 cm.

Breadth of rectangle = x = 4.5 cm .

Answer 2

Answer:

l = 13.5 cm

b = 4.5 cm

Step-by-step explanation:

$\underline{\bigstar\:\textsf{Given:}}$

• Ratio of length and breadth of a rectangle = 3 : 1
• Perimeter = 36 cm

$\underline{\bigstar\:\textsf{To\:find:}}$

• Length and breadth (l and b) = ?

$\underline{\bigstar\:\textsf{Solution:}}$

Let the actual length and breadth be 3x and x respectively.

We know perimeter of a rectangle = 2(l + b)

➳ 36 = 2(3x + x)

➳ 18 = 4x

➳ $\sf{\dfrac{18}{4}\:=\:x}$

➳ 4.5 = x

Now we know the value of x,

Length = 3x = 3 × 4.5 = 13.5 cm

Breadth = x = 4.5 cm