There are three switches outside a room that control three light bulbs inside the room.  The door to the room is closed and the lights cannot be seen from the location of the switches. You may turn on/off any switch freely prior to entering the room, but you cannot change the switch position after making your final selection and entering the room only once.

With complete certainty, you can tell which switch controls which light…but how?

Give up?….(play video for solution)

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Video by Runyu Xia

Runyu is a Senior Designer at Essense and is our resident motion graphics expert. He has storyboarded and developed numerous videos on behalf of our utility clients.

Prior to joining Essense, Runyu was a motion graphics designer at Touch Tunes Interactive Network. He was also lead web designer for and was a graphics designer at Tri-Coastal Design in New York City.

Runyu is fully skilled in Adobe Photoshop, Adobe Illustrator, Adobe After Effects, Adobe Premiere, Sketch and Axure. He has a MFA from the School of Visual Arts in New York, and received his Bachelor of Engineering in Art and Technology from Shanghai University.