Question

the length of a rectangular field is thrice it's breadth it's perimetre is 400m what are its dimensions

Answer 1

let breath be x
so length will be 3x
perimeter of a rectangle is 2(l+b)
but here perimeter = 800m
therefore 2(3x+x) = 800m
that equals to 2(4x)=800m
8x=800m
therefore x=800/8
that equal to x=100
now substituting the value
3x=300
x=100
so length=300m
and breath=100m
now area of rectangle = l * b
=> 300*100
=> 30,000msq.

Hope This Helps :)

Answer 2

let b = x m
a/q l = 3x m
p=2 (l+b)
400=2 (x+3x)
400/2=4x
x=200/5
hence x= 40m
so length= 120 m
breadth = 40 m