Diameter of Flying SaucerDate: 5/27/96 at 10:57:19 From: Anonymous Subject: Diameters of Flying Saucers Dear Dr. Math, I need some help on a landscaping project... We are constructing an oval racetrack in Atlanta, and while excavating for the project, we ran across a large circular object buried in the ground edgewise. The portion that we have uncovered so far measures 10 meters high by 30 meters across. We have not dug down far enough to get a measurement on the diameter of this saucer-like object. But we need to know the diameter so that we can tell how far down we have to dig to get it out of the ground. We don't want to spend too much time with this thing. It is radioactive... Thanks! Date: 5/27/96 at 21:11:2 From: Doctor Ken Subject: Re: Diameters of Flying Saucers Hello! The first thing you need to do is hire someone else with a yellow plastic suit to do your digging for you - no telling how your children will look with all that radioactivity leaking around. So let's assume this flying saucer is indeed saucer-shaped (several of the flying saucers I've unearthed have looked like they were going to be saucer-shaped at first, but sometimes when I dug up the whole thing there was actually a big nose cone sticking directly downward, like the craft took a nose dive into the ground. I guess they haven't figured out how to land on our planet yet - perhaps their planet is softer!). I've made a picture of the saucer, and you can see it on the web at: With the parts labeled as I have them in my picture, you've measured the length of AC (it's half of 30, which is 15) and BC (which is 10). And you want to figure out the radius of the circle. Well, notice that DA and DB are both radii, so they have the same length. You can call that length R. Now look at the green triangle, triangle ACD. It's a right triangle, and the top leg has length 15. The hypotenuse has length R, and the other leg has length R-10. Can you use the Pythagorean Theorem to figure out R? Good luck! And if you find any non-Earth creatures inside, tell them Doctor Ken says howdy. -Doctor Ken, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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