Length = 90 inch.
width = 30 inch
Let width of the rectangle = x inch.
So the length = 3x inch.
Perimeter = 2(length + width) = 2 (3x + x) = 8x.
So,
[tex]8x=240\\ x=30[/tex]
So length = 3x = 3(30) = 90 inch.
width = x = 30 inch
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