The perimeter of a rectangle is 48 in. If the length is twice the width what is the length of the rectangle?

Length##=16## inches
Let ##l## be the length and ##w## width.
It is stated that ##l=2w…………….(1)##.
Now the perimeter of the rectangle##=48##.
## rArr 2(l+w)=48 or l+w=24##
## rArr 3w=24……………[by(1)]##
##:. w=8 & so l=2w=16## inches.