Brain Teaser April 2018

Alan Kinker is a long-time Porsche owner and member of the Maumee Valley Region Porsche Club of America. He and his wife Sandra have planned and attended a number of MVR Driver Education events over quite a few years. Alan, a retired military pilot (Thank you, Alan!), is an engineer working in the racing industry. One weekend, on a warm, comfortable afternoon, he decides to pull the 914 out of the garage and give it a good spring cleaning - outside and in. Sandra, seeing the great work done on the car, encourages Alan to also clean out and re-organize his tool chest. 

With a chagrined smile, Alan dives in. Looking in one particular tool chest drawer, he finds three mason jars - each filled with 12 bolts and accompanying nuts. 

Answer

One jar has all small sized bolts/nuts, one has medium sized bolts/nuts, and the third jar has six of each size.  Each jar has a handwritten mark on the lid that identifies the sizes:  “small”, “medium”, “both”. The problem is, each lid is incorrect – at some point in time Alan (or maybe it was Sandra!) put the lids on the wrong jars.

Alan, who is particularly good at puzzles, quickly solves the “wrong lid conundrum”.  Knowing he can reach into any jar and pull out just one bolt/nut, what is the fewest number of jars he opened to put the lids back on correctly?