Solution :D

Posted by HeroofTime55 on Dec. 5, 2006, 7:30 p.m.

In response to this, posted by C-Actor9:

OK, so first, I assume that in both the pictures one of the faces is paralell to the ground (the top in the first, bottom in the second). Going off my 1337 math skillz, I realize that the triangles are equilateral, and thus also the triangular prisim formed by the water occupying the first. Such a triangle is made of 2 30-60-90 triangles. The sides in such are (I think) 1, 2, square root of 3. Therefore the length of the sides of the triangle formed by the water are 2. The volume of the water is 16*3^(1/2).

Anyhow, I'm halfway there. Now, I just need to calculate the height of the trapezoidal prisim on the bottom. First, the area of one of the ends is the same 2*3^(1/2) from before, by dividing by 8. Actually, since the two ends are paralell, a third dimension was not actually required for this problem, though it makes a prety picture.

So, I drew a picture myself to keep track of everything (of course, not drawn to scale):

Now, here's the fun part. You combine the two 30-60-90 triangles into one rectangle. So, now you have a rectangle of dimensions X*whatever, and an area 2*3^(1/2). Now, it's a "simple" solve for X problem, in really ugly notation due to lack of symbols on a keyboard/not knowing the proper codes to enter.

-1/(2*3^(1/2))*X^2 + 8X - 2*3^(1/2) = 0

I got two decimal answers from my Quadratic formula program:

X = .4399985956

X = 27.27281433

Obviously, the height is not 27, which is far beyond the capacity of the prisim, and therefore, the answer is .4399985956 units high.

For a more exact answer, I can use the quadratic formula:

(-B+-(B^2-4AC)^(1/2))/(2A)

Which becomes:

(-(8)+-((8)^2-4(-1/(2*3^(1/2)))(2*3^(1/2)))^(1/2))/(2(-1/(2*3^(1/2))))

Which simplifies into:

(-8+60^(1/2))/(-3^(-1/2))

(The solution (-8-60^(1/2))/(-3^(-1/2)) is about 27, outside the bounds of the prisim)

And, there you have it.

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In other news, nobody yet has solved the two secret messages in my Mario Kart DS icon:

Giant cyber cookies to whoever does it. One of the messages is the numbers, the other is the dots along the bottom.

Comments

foslock 17 years, 10 months ago

If I have a math problem… I am coming here.

Giant Cyber Cookies give me cramps.