Answer:
The actual length of the porch is 18 feet.
Step-by-step explanation:
Scale =

So that considering the width of the drawing and actual porch,
1 foot = 12 inches
12 feet = 12 x 12 inches
= 144 inches
scale =

=

Given that the length of the porch drawn is 12 inches, let the actual length of the porch be represented by x. Then the actual length can be determined by;
scale =

=

x = 12 x 18
= 216
x = 216 inches
But,
1 foot = 12 inches
216 inches = 18 feet
The actual length of the porch is 18 feet.