Question

the perimeter of the rectangle is 13 cm and its width is 2 3/4 cm find its length.​

Answer 1

$\large\mathfrak{ \underline{ \underline{Correct \: question:-}}}$

The perimeter of a rectangle is 13 cm and its width is $\large{2 \frac{3}{4}cm. }$Find its length.

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$\huge{ \mathtt{GivEn:-}}$

• The perimeter of a rectangle = 13cm.
• The width of the rectangle =$\large{2 \frac{3}{4} cm}$

$\large{ \mathtt{NeEd \: tO \: fiNd:-}}$

• The length of the rectangle.

$\large \underline{ \mathtt{ \red{ \: ExplaNatiOn:-}}}$

Let the length of the triangle be x cm.

As we know that;

$\small\boxed{\bold{ \pink{PeriMeter \: oF \: thE \: triaNgle = 2 (l + w)}}}$

$\large \implies{2 \times (x + 2 \frac{3}{4})} \\ \large \implies{ \bold{2(x + \frac{11}{4} )}}$

$\small{\boxed{\mathtt{ \bold{ \purple{\: PeriMeteR \: oF \: thE \: rEctaNgle = 13cm}}}}}$

Therefore,

According to question;

$\large{ \implies{2(x + \frac{11}{4} ) = 13}} \\ \large{ \implies{x + \frac{11}{4} = \frac{13}{2} }} \\ \large{ \implies{x = \frac{13}{2} - \frac{11}{4} }} \\ \large{ \implies{x = \frac{26}{4} - \frac{11}{4} }} \\ \large{ \implies{ \frac{15}{4} }}\\ \large{ \implies{ \bold{3 \frac{3}{4}cm}}}$

$\small{ \mathtt{Hence,the \: length \: of \: the \: rectangle \: is \: 3 \frac{3}{4}cm. }}$

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Answer 2

Answer:

As we know,

perimeter of rectangle=2× (l+b)

Therefore, 2×(2 3/4+b)

Now again as we know, perimeter=13cm

Therefore,2 (2 3/4+b)=13

2(11/4+b)=13

11/4+b=13/2

b=13/2-11/4

b=13×2/2×2-11/4

b=26/4-11/4

b=15/4cm

Hope it helps you..