Question

9. The perimeter of a rectangular field is 3/5km and its length is twice its breadth. Find the

area of the field in m²​

Answer 1

Answer:

720000 m2

Step-by-step explanation:

given:

breadth = 3/5 km = 600 m

length = 2×breadth = 2×600 m = 1200 m

According to question,

Area of the field = length × breadth

= (1200×600) m2

= 720000 m2

Hence, the area of the field is 720000 m2.

Answer 2

Given :–

• The perimeter of a rectangle field = $\sf \dfrac{3}{5}$ km.
• The length is twice it's breadth.

To Find :–

• Area of the field in m².

Solution :–

Let,

The length of a rectangular field be x.

The breath of a rectangular field be 2x.

First, we need to convert km into m.

For converting, we need to multiply the given value by 1000m.

So,

$\longmapsto \sf \dfrac{3}{\cancel5} \times \cancel{1000}$ m

$\longmapsto\sf 3 \times 200$ m

$\longmapsto\sf 600$ m

Perimeter = 600 m

$\longmapsto2(l + b) = 600 \: m$

$\longmapsto2(x + 2x) = 600 \: m$

$\longmapsto x + 2x = \frac{ \cancel{600}}{ \cancel2} \: m$

$\longmapsto3x = 300 \: m$

$\longmapsto x = \dfrac{ \cancel{300}}{ \cancel{3}}$

$\longmapsto x = 100$

So,

The length of a rectangular field = x = 100m.

The breadth of a rectangular field = 2x = 100m × 2 = 200m.

Now,

$Area \: of \: a \: rectangle = l \times b$

• l = 100m.
• b = 200m.

$\longmapsto100 \times 200 \: {m}^{2}$

$\longmapsto20000 \: {m}^{2}$

Hence,

The area of a rectangular field is 20000 m².