# Fuzzy Mathematics (Extra Credit)

• Let’s say you are given nine identical-looking eggs and told that one is heavier than the others, but you  are not told which one.  Fortunately, you have a beam balance for comparing the masses of the eggs.  Unfortunately, the balance is a rental, and you are being charged each time you use it.  So assuming you are strapped for cash and wish to know which of the nine eggs is heaviest - who wouldn’t? - what is teh minimum number of times you must weigh the eggs in order to find it?

The answer, it may surprise you to learn, is only twice.  Here’s how: First divide the eggs into groups of three and compare the masses of two groups; if one trio is heavier, simply compare two eggs from that one and you’re done. (If the two balance, then the third is heavier.) On the other hand, if the two triplets you weighed have the same mass, compare two eggs from the trio you initially left out!

(9-6)-(2+1)=the heavier egg!

Probably wouldn’t surpise you if I told you that out of the 256 students who saw this on the test only 17 got it correct. Then again, it was only a 5% extra credit question on the exam. (Algebra.)

• Never would’ve gotten that one … Math is my worst subject however.

• I could of gotten the answer but never be able to use algebra to show how i got 2 times.  this was for 8th grade?

• And to think, I have chickens here, on the farm. Eggs…… The other white meat…

• Yea, Jr. High School Algebra Class.

Honestly, it’s tough because it’s Extra Credit.  I don’t like to give away EC points. But if you can handle it, great!  Not everyone is created equal, some are just better then others at certain tasks!  And if you can figure out problems like that, in the 8th grade, then you deserve the recognition and the credit!

BTW, I don’t curve either.  Even though it is “recommended” (ie, I get yelled at every quarter for not doing it) to curve grades so that 80% of the class gets a B or better.  Again, you get what you earn.

• I wish you left out the answer…

Honestly, I don’t know how you would solve that algebraicly.  It occurred to me that you could use more than one egg, but then I read the answer.

• The purpose of the curve is to offset the effect of a particularly challenging subject matter and/or a poor teacher. If in a particular class, otherwise good students consistently perform poorly, then while it may be that they just aren’t putting the effort into it, a more likely explanation is either that the subject matter is simply above them, or the teacher is not up to the task. The curve balances this effect out.

My point in saying this is only to say that a curve does have a legitimate purpose, though I am with you, Jen, in opposing its wanton use. In the case of junior high classes, courses that are offered as “Honors”, “High”, etc., the above-average classes, a curve should be employed only if the whole class consistently does poorly.

• I’m the best teacher in the world. (Hey, you’ll never be if you don’t think you are!)  I don’t need no stinkin curve.

Actually, to be honest, most of my students score around the 70-75% mark.  The rest fall between 85% and 60%.  Very few get As, very few get Fs.

As for posting the answer, I had considered holding it for a week then posting it, but I decided against it…Thought it would be more fun for people to see the answer right away.  However, for the next one I’ll either hold off or put a lot of carriage returns in so that it is not appearing right away.  Okay?

• 248 dimension problem?  That’d be pretty tough for anyone to figure out.  However, if I read the proof I think I’d understand the vast majority of what was being said.

Why?

• @AJGundam:

Could you figure out this problem?
http://news.yahoo.com/s/livescience/20070319/sc_livescience/brainiacssucceedinmapping248dimensionalobject

hah ah that is funny. i have problems drawing 3-d objects let alone 284-d.

• Imagine building one!  The tessaract from hell! (I probably mispelled it) the tessaract - for those who do not know - is a physical representation of a 4-D object in a 3-D world…or at least the best hope of making one. hehe.

• 248 dimension problem?  That’d be pretty tough for anyone to figure out.  However, if I read the proof I think I’d understand the vast majority of what was being said.

Why?

Just wondering how smart you realy were

• @AJGundam:

Could you figure out this problem?
http://news.yahoo.com/s/livescience/20070319/sc_livescience/brainiacssucceedinmapping248dimensionalobject

SHuurre!!!

HHhand mee that cocktail nakpin…

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