The perimeter of a rectangular blanket is 18 feet.What could be it's length and width?

2l + 2w = 18

l + w = 9

could be any two positive numbers that add up to 9
e.g.
5 and 4
7.5 and 1.5
3 2/5 and 4 3/5
6.123 and 2.877
As you can see there would be an infinite number of possibilities.