The robot starts on square 25, initially facing square 32. The robot (i) moves 2 squares forward in the direction that it is facing, (ii) rotates clockwise 90∘, and (iii) moves 1 square forward in the new direction. Thus, the robot moves to square 39, then turns to face square 38, then moves to square 38. The robot repeats the sequence of moves (i), (ii), (iii) two more times. Given that the robot never leaves the grid, on which square does it finish?
Pick one
Solution
Starting at 38, the robot moves 2 squares forward to 36, then rotates 90∘ clockwise to face 29 and then moves to 29.
Starting at 29, the robot moves 2 squares forward to 15, then rotates 90∘ clockwise to face 16 and then moves to 16.
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