Question

The length of a rectangular field is thrice its breadth. If the perimeter of this field is 800m, what is the length of the field?

Answer 1

let breadth be X
so length will be 3x
perimeter=800m
perimeter=2×(l+b)
800=2(X+3x)
800=2×(4x)
800=8x
X=800÷8=100

thus breadth =100 m
and length = 300m

Answer 2

The length of a rectangular field(l) is 300 m.

Step-by-step explanation:

Let breadth of a rectangular field(b) = x

The, length of a rectangular field(l) = 3x

To find, the length of the field = ?

We know that,

The perimeter of rectangle = 2(l + b)

⇒ 2(3x + x) = 800

⇒ 2(4x) = 800

⇒ 8x = 800

⇒ $x=\dfrac{800}{8}=100$

∴ The length of a rectangular field(l) = 3 × 100 m = 300 m

Hence, the length of a rectangular field(l) is 300 m.