GeekDad Puzzle of the Week: Pedro Vex and the Bad Electrician - Solution!

Congrats to Glenn W. who correctly answered the puzzle and nets a a $50 gift certificate from ThinkGeek!

Super spy extraordinaire Pedro Vex has returned home to his fortress of solitude for a nice relaxing vacation. While he was gone, he had some electrical work done on his house by a government contracted electrician, so he’s not quite confident in the work. Before he can relax, he’s been walking around the house checking all the light switches and electrical outlets. Finally he comes to the last room, the den. Turns out, the electrician moved the light switches for the den into the panic room, which is out of sight of the den. And Pedro knows once he enters the panic room and fiddles with the switches, he’ll activate the fail safe and only have a couple minutes (it’s a really heavy door) to get out of the panic room back into the house before being locked in the panic room. Basically, he has only one chance to flip switches. There are three switches (A, B, C) and three table lamps in the den (1, 2, 3.) Each switch is connected to one lamp (the lamps are basic lamps with one 100 watt bulb in each.) Pedro only gets one chance at flipping the switches (in whatever order he chooses.) Which switch is connected to which lamp and how can he tell?

Yes, most of you were correct. This is a classic psychology question used on many tests from job applications to college exams. I just twisted it a little to the tale being told.

The correct answer, from Glenn.

Here's how Pedro should handle it:

Pedro flips switch #1 ONPedro flips switch #2 ONPedro keeps switch #3 OFFJust before the panic room door closes, Pedro flips switch #2 OFF and darts out the door using his Amazing Spy Gymnastics (like Gymkatabut less hand chalk). Pedro proceeds to the den.The lamp that is ON is controlled by switch #1.The lamp with the warm bulb is controlled by switch #2.The lamp that is OFF is controlled by switch #3.Pedro makes himself a martini and plots his revenge against the inept government electrician.

Aside from the right answer above, there were some very creative solutions, and one made me laugh out loud when I read it. While it didn't win - I feel the need to share this readers' creativity with the world.

Pedro removes the bulbs from the lamps. He then invites three friends over: Al, Ben and Charlie. Al, Ben and Charlie stick their fingers in the light sockets of lamps A, B and C, respectively. Pedro then proceeds to the danger room and flips switches 1 – 3. Pedro, carefully trained in the art of voice analysis, then deduces which switch is connected to which friend, err… lamp, by the yelps he hears. - Eric B.

Thanks for playing! Please come back next week for another puzzle! Don’t forget to take $10 off a $40 or more purchase from ThinkGeek by using the code, GEEKPUZZLER.