Brainteasers – Issue 37, 2017

Many of our readers have told us that once they receive their copy of Automation Notebook, The Break Room is the first section they read. But, you have to be careful not to get so caught up into it that you leave the rest of Automation Notebook behind. Take a mental break for a few minutes and see if you can solve these puzzles. Then go to your coworkers and see if you can stump them.

1.) Fence Me In!

The puzzle factory has twenty robots on the factory floor, laid out as shown on a grid. The safety manager wants to install fencing on the plant floor to isolate the robots into separate work cells. The plant manager agrees, but only if it can be done with six (and only six) straight sections of fence. Can you determine where the six straight fence sections should be placed?

 

2.) Can’t Touch This

Can you position six Edison fuses so that each one is touching all of the other five? We’re told it can even be done with seven (with each touching the other 6, of course)?

Remember that we have great prices, and fast shipping for all your fuse, fuse holder, and circuit protection needs! To learn more, visit: www.automationdirect.com/circuit-protection

 

3.) Month of Sundays

There have been a number of (false) rumors going around the internet about how rare it is for a certain month to have 5 weekends. The time frame of 823 years is often quoted, and you will purportedly get rich that month IF you forward the email to 5 or 10 of your friends. That last part is a dead-give-a-way that something is rotten in Denmark, right? Five-weekend-months happen pretty often – April (2017) will be one (and with only 30 days in that month).

If you want to include 5 Fridays with those 5 weekends, you only have to wait until this December (2017).

On a related note, we’ve seen questions and posts asking about years that have Februarys with five Wednesdays (or any other day of the week, for that matter). Obviously, that requires the year in question to be a leap year, and

February 1st of that year must fall on a Wednesday (or your favorite day-of-the-week). One question that is often posed, “Find the probability that the month of February may have 5 Wednesdays in A) a leap year, and B) a non-leap year.” Not a bad question, but not really a difficult problem to solve either. Let’s make it more of a challenge: What is the probability that ANY given year will have a February with five Wednesdays? (Remember that leap years don’t fall EVERY four years – just mostly every four years.

Puzzle concepts credited to:
Henry E. Dudeney