[Elecraft] OT: math question

[Dan Barker]

I ran into a brain-teaser once, that had me baffled for hours (I won't say
how many). Finally, I called my sister, the Rocket Scientist ("actually,
we're not _Rocket_ scientists" - That's a quote from her husband) and asked
her.

She and Paul spent a few minutes on the problem, figured it out, but it was
such a trivial answer they threw it away. Since I'd spent so long on the
Question, I gave her about a week and then I called back. Luckily they'd not
taken out the trash, so she easily found their notes and read them to me.

I won't spoil it for you 'crafters.

Dan / WG4S / K2 #2456

Problem: An alley has a 20-foot ladder across it, in the left lower corner
and leaning on the right wall. There also is a 30-foot ladder, from the
right lower corner leaning on the left wall. The laders cross at 10 feet
high.

How wide is the alley?

Usual conventions: alley is all right angles, ladders have no thickness nor
bends, blah blah blah...

This should make some juices flow out there. Just simple geometry, or is it?


PS: Iteration is cheating. Sorry Issac.


<snip>
 the responses would be far more interesting than merely "looking up" the
answer
</snip>