Sixteen squares are arranged to form a region, as shown.
Each square has an area of 400 m 2. Anna walks along the solid line path formed by the outer edge of the region exactly once. Aaron walks along the dotted line path formed by the inner edges of the region exactly once. In total, how far did Anna and Aaron walk?
Pick one
Solution
Each of the squares that has area 400 m 2 has side length 400 = 20 m.
Anna’s path walks along exactly 20 side lengths of squares, so has length 20⋅20=400 m.
Aaron’s path walks along exactly 12 side lengths of squares, so has length 12⋅20=240 m.
Therefore, the total distance that they walk is 400+240=640 m.
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