GMAT Problem Solving (PS) | Re: Martin planted a rectangular garden with dimensions 20 feet by 30 feet

Martin planted a rectangular garden with dimensions 20 feet by 30 feet and then surrounded the garden with a rectangular brick walkway of uniform width (represented by the shaded area in the drawing above). If the area of the walkway equals the area of the garden, what is the width of the walkway?

(A) 1 foot
(B) 3 feet
(C) 5 feet
(D) 8 feet
(E) 10feet