Iowa Jones
Fine Eye Times
475 Second Street
Big City, PU 11248-1632

March 24, 2008
 


Calculus Student
Franklin & Marshall College
Lancaster, PA 17604


Dear Calculus Student,

I  know you don’t even know who I am, but I hope for Will’s sake that you can help us out of a big jam!  I’m afraid that Eve might have kidnapped Will and locked him in an underground chamber! You’ve got to help  me figure out how to get him out! 

I’m Iowa Jones, by the way.  I only met Will about a month ago, but there was something about him that just drew us together.  I was sitting on a bench outside of Vellen Enterprises, trying to figure out where I could look for a new job.  (Eve had just fired me for letting it slip in front of a customer that our tanks are parabolic instead of hemispherical).  Bill saw me sitting there and stopped to cheer me up, which was hard for him because he was pretty depressed about how Eve had been treating him, too.

As we talked, we began putting together bits and pieces of a giant puzzle, and we came to realize that for about a year now, Eve has been hatching a vile scheme to take over the world, one shoe at a time!  It began when Will started working for his grandfather.  You remember he moved from department to department when he started there.  In one of those departments, Will developed a new kind of rubber that can be used in boat shoes.  Unknown to him at the time, these rubber soles became a huge phenomenon.  You might have heard of these:  Blezz Shoes sold them under the jingle:

    Xeno’s Boat Shoes:  Get your own pair o’ docksiders!

For a while, everywhere you went, you’d hear people humming about Xeno’s pair o’ docks.   They were amazing!

What made them so amazing -- and ironically, what has me stumped right now -- is that the rubber soles are astonishingly elastic, with an 81% bounce coefficient.  (That means that if you drop a shoe without anything in it, it will bounce back to 81% of the height you dropped it from.  If you don’t think that’s amazing, try it with your own shoes).  These shoes put a real spring into everybody’s step for as long as the shoes were on the market.

But then Eve happened. 

Eve stole the rubber recipe for from Blezz by using an elaborate ruse (she sold Blezz Shoes a rubber-making machine and then bought it back full of their rubber).  She had me hack into their computers to destroy their own records of how to make the material.  And then she devised a scheme to bankrupt the company by convincing them to invest in storage tanks that were smaller than required by industry standards. 

Why did she do all this?  As I said, she has an evil scheme to take over the world -- I don’t want to put your own life at risk by telling you all the nefarious details.  We should have realized, though, that Will was in danger, because the only remaining rubber recipe outside of her control was in his head!  We underestimated her, and we were totally unprepared when her henchmen broke into his apartment and abducted him.

I’ve been able to hack back into the Eve L. Vellen system, so I know where she’s keeping him:  he’s strapped to the wall about half-way up one of her vacant parabolic tanks!  I also figured out the code that I will need to enter into the computer to unlock the doors and let him out.  There are two parts to this code:  a simple password to enter the system that monitors the release mechanism, and a longer sequence of  code that actually accomplishes the release.  So I’m almost all the ready to free him!

But here’s the problem.  There’s an elaborate security device that Eve installed, hoping to thwart rescue attempts like mine.  This is how it goes.

I enter the first part of the security code, which is just a simple password.  That password not only lets me enter into the system, however; it also automatically releases one of Xeno’s shoes from the top of the tank, and the shoe falls 100 feet to the bottom of the tank, where there’s a delicate sensor.  From there, the shoe bounces up and down, with each bounce 81% as high as the previous one.  Exactly 1 minute after I enter the password, the second shoe drops, and it too starts bouncing.  And then exactly 2 minutes after I enter that first password, if I haven’t already entered the second sequence of code, the system automatically releases a deadly poison that will kill Will within seconds!

So, clearly I have to enter that second sequence of code within the first 2 minutes.  That ought to be easy: I’ve practiced over and over on a keyboard that’s not plugged in, and I’ve got it to the point where I can do it in 9 seconds flat.  However there’s one more twist (I swear, Eve watched too much Batman when she was a kid)!  If the sensor detects a bounce while I’m in the process of entering that sequence of code, It triggers the poison gas, and Will dies.

This means I’ve got to figure out if there’s any 9-second window (or even a little longer?) with no bounces at all.  Maybe I could enter the code while the first shoe is falling?  Or while it’s bouncing the first time?  I know that once these shoes start bouncing, they keep bouncing faster and faster, and they do this for a long time -- am I right that there’s no time between the two shoes to enter the code?

I know that Will trusts you.  Is there any way that you could help us out again?  I hate to bother you, but on the other hand the fate of the entire world depends on this!

I think I’ve found my sole mate.

Yours sincerely,

Iowa Jones


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