Answer:
l = 2 1/2 ft
Explanation:
Area is given by the formula
A = l*w
We know the area is 8 1/2
Changing this to an improper fraction 8 1/2 = (2*8 +1)/2 = 17/2
The width is 3 2/5 as an improper fraction = (5*3+2)/5 = 17/5
A = l*w
17/2 = l* 17/5
Multiply each side by 5/17
17/2 * 5/17 = l* 17/5 * 5/17
5/2 = l
2 1/2 = l