The Light Switches Brainteaser

Firms are going to use tricks like this to try to weed out people who freeze, but if you stop and think about it, most of the questions you are ever asked on an interview are pretty logical.  You just have to take a moment.  Take a deep breath.  Don’t be frozen because someone is sitting there and watching you.  Just use that brain of yours and figure it out. 

You’re going to enter a room.  There are 3 light switches.  You can only enter one time and which switch controls which bulb? 

Now, you cannot use the obvious dumb answer– turn on each switch and you’ll know which one does it.  You have to figure it out a little differently.

So, this is how the answer works.  You turn on two switches and leave them on for a while.  Then, what you do is turn off one switch.

Now, obviously, the bulb that still on is controlled by the switch that you turned on stayed on, right?  You, then, touch the other bulbs the ball that’s warm is controlled by the switch you turned off, right?

Then, the 3rd switch controls the 3rd bulb.  It’s very easy, isn’t it?


Ⓒ The Big Game Hunter, Inc., Asheville, NC 2020



Jeff Altman, The Big Game HunterJeff Altman, The Big Game Hunter is a coach who worked as a recruiter for what seems like one hundred years. His work involves career coaching, all as well as executive job search coaching, job coaching, and interview coaching. He is the host of “No BS Job Search Advice Radio,” the #1 podcast in iTunes for job search with more than 1800 episodes, and is a member of The Forbes Coaches Council.

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Jeff Altman, The Big Game Hunter
Jeff Altman, The Big Game Hunter

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