Question

Q. The perimeter of a rectangle is 240 cm if the breadth of the rectangle is 30 cm find its length also find the area of rectangle​

Answer 1

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Perimeter of the rectangle = 240 cm

Breadth = 30cm

Length = ??

We know that,

Perimeter of a rectangle = 2(l + b)

=> 240 = 2(l + 30)

=> 240/2 = l + 30

=> 120 = l + 30

=> l = 120-30

=> l = 90cm.

Hence, we got length as 90cm

Area of the rectangle = l*b

= 90*30

= 2700cm² ans.

Answer 2

Answer :

›»› The length of a rectangle is 90 cm.

›»› The area of a rectangle is 2700 cm².

Step-by-step explanation :

Given :

• Perimeter of a rectangle = 249 cm.
• Breadth of a rectangle = 30 cm.

To Find :

• Length of a rectangle = ?
• Area of a rectangle = ?

Formula required :

Formula of perimeter of rectangle to find the length of a rectangle is given by,

→ Perimeter of rectangle = 2(l + b).

Here,

• l is the Length of rectangle.
• b is the breadth of rectangle.

Units,

• The unit of length is centimetre (cm).
• The unit of breadth is centimetre (cm).

Formula to find the area of rectangle is given by,

→ Area of rectangle = l * b.

Here,

• l is the Length of rectangle.
• b is the breadth of rectangle.

Units,

• The unit of length is centimetre (cm).
• The unit of breadth is centimetre (cm).

Solution :

Let us assume that, the length of a rectangle is x cm.

We know that, if we are given with the perimeter of rectangle and breadth of rectangle then we have the required formula, that is,

→ Perimeter of rectangle = 2(l + b).

By using the formula of perimeter of rectangle to find the length of a rectangle and substituting all the given values in the formula, we get :

→ 240 = 2(x + 30)

→ 240 = {(2 * x) + (2 * 30)}

→ 240 = 2x + (2 * 30)

→ 240 = 2x + 60

→ 240 - 60 = 2x

→ 180 = 2x

→ x = 180/2

→ x = 90.

Hence, the length of a rectangle is 90 cm.

Now,

We know that, if we are given with the length of rectangle and breadth of rectangle then we have the required formula, that is,

→ Area of rectangle = l * b.

By using the formula to find the area of rectangle and substituting all the given values in the formula, we get :

→ Area of rectangle = 90 * 30

→ Area of rectangle = 2700.

Hence, the area of rectangle is 2700 cm².