Question

A rectangular plot measures 20 ft. by 30 ft. a 3-ft.-wide sidewalk surrounds it. find the area of the sidewalk. 936 ft.2 600 ft.2 336 ft.2

Answer 1

(20x30)= 600
that's the area of rectangular plot

3ft wide sidewalk means both +3 on left and +3 on right, also both +3 up and +3 down

which means u have to do 26x36=936

then subtract 
936-600=336 square feet