O, yeah, Found the N now
brainteasers
- denne
- Thread is marked as Resolved.
There are 148 replies in this Thread. The last Post () by (IOC)Wanderer.
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60
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cool ... that's correct.
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I get it now, nice one
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i found 40.
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i found 27
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I keep getting 36
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i think 40 is correct
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40
1x 4x4
4x 3x3
9x 2x2
18x 1x1
8x 0.5x0.5 -
From the funny pics thread:
= 100% * [1 - (hl/h2)^3].But I would do it the following way:
Then I get:
Any mistakes here??
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i only see one part which looks fishy
but well, that never was my strength. -
Guess I must answer this one myself
Mistake 1:
=100%*[1-(hl/h2)^3] is the wrong result (I took h2 as the variable), the correct one is =100%*[1-(hl/h2)] (all integrands are the same constant that can be reduced).Mistake 2:
The expression in the funny picture is wrong - its result depends only on hl and h2, while it must also depend on r1 and r2 (otherwise we get identical %Vl for glasses of any shape as long as they have the same hl/h2).Everything else was correct My roommate who loves maths has suggested a way to get a better looking answer:
It could be also obtained without integration if we looked up a formula for a truncated cone: V = 1/3 * Pi * h * (r1^2 + r1*r2 + r2^2) = 1/3 * Pi * h * (r2^3 - r1^3)/(r2 - r1).
But this would apply only to the particular case of a conical glass, while the previous method will work for any axysimmetric body defined by an integrable function r(h).Hope all is clear now
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whatever
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yeah, now that u say it
i'm sorry, i didn't even try
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No problem That picture was not only funny but also gave us some brain exercise - thank you for finding it
Edit:
Another creative solutionEdit 2:
And one more -
and an engineer, the glass is twice too large that it should be
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●☆○ I think it's 25