#### Answer

3 $ft^{2}$

#### Work Step by Step

The ratio of the perimeter is the same as the ratio of corresponding sides. This is given as 1:3.
The ratio of the areas is the square of the ratio of corresponding sides.
$1^{2}$:$3^{2}$=1:9
Set up a proportion based on this ratio
$\frac{1}{9}$=$\frac{x}{27}$
Cross Multiply
9x=27
Divide both sides by 9
x=3