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Messages 11729 - 11758 of 13927   Oldest  |  < Older  |  Newer >  |  Newest
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11729
Suppose that M is an integer with the property that if x is randomly chosen from the set { 1, 2, 3, ..., 999,1000 }, the probability that x is a divisor of M...
dwittman@...
derekwittman
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Jun 4, 2006
6:46 pm
11730
Now that I know how to divide up a sphere into four equal pieces, using the tetrahedron to find the vertices, how can I general that to other numbers of equal...
MorphemeAddict@...
lojbaner
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Jun 4, 2006
8:04 pm
11731
Maybe it's a silly solution, but the watermellon idea "naturally" gives me this: with a regular dipyramid aka two pyramids glues by theis bases (bases are ...
Sergio Frosini
topometallo
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Jun 5, 2006
9:32 am
11732
A number plus its three digits equals 1005. What is the number?...
cooperpuzzles
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Jun 5, 2006
10:03 am
11733
Another way to state this method: Cut the watermelon the same way you would cut a circle into n congruent pieces. That is n radii with their outside ends...
cooperpuzzles
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Jun 5, 2006
10:38 am
11734
... 984 Peter...
Peter Otzen
bogaduck
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Jun 5, 2006
11:13 am
11735
... Or do you mean a sneaky 1002 - whose three [different] digits are 0,1 and 2. Peter...
Peter Otzen
bogaduck
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Jun 5, 2006
11:14 am
11736
That was going to be my next question. John...
cooperpuzzles
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Jun 5, 2006
11:42 am
11737
In a message dated 6/5/2006 4:32:58 AM Central Standard Time, ... Drat! I forgot all about that. That's even the way I normally cut a watermelon. stevo ...
MorphemeAddict@...
lojbaner
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Jun 5, 2006
1:54 pm
11738
In a message dated 6/5/2006 5:04:00 AM Central Standard Time, ... 1005=a*100 + b*10 + c + a + b + c 1005= a*101 + b*11 + c*2 a=9 1005=909+b*11 + c*2 ...
MorphemeAddict@...
lojbaner
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Jun 5, 2006
1:55 pm
11739
... Yes, in lots of ways. :) I'm assuming pieces can overlap on their boundaries. If you disallow this, I'm pretty sure you get into open questions very...
adh_math
Offline
Jun 5, 2006
2:47 pm
11740
On the subject of dissecting spheres into congruent pieces, here's a very nice gallery of temari (Japanese thread ball folk art) ...
adh_math
Offline
Jun 5, 2006
3:08 pm
11741
... Or more succinctly: Find the largest integer M < 1000 that has exactly ten divisors (including 1 and M). If M = (p1^k1)*(p2^k2)*...(pn^kn) is the prime...
adh_math
Offline
Jun 5, 2006
3:33 pm
11742
... Try it on 1008,1019,1030, 1023,1025,1027,1029,1031...
cino hilliard
hillcino368
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Jun 5, 2006
4:44 pm
11743
In a message dated 6/5/2006 11:44:49 AM Central Standard Time, ... So far I have f(990)=1008 f(CCC)=1019 base 13 f(666)=1023 base 7 f(AAA)=1027 base 11 I'm...
MorphemeAddict@...
lojbaner
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Jun 5, 2006
5:23 pm
11744
In a message dated 6/5/2006 12:23:59 PM Central Standard Time, ... Should be f(CCC)=1029 base 13. stevo [Non-text portions of this message have been removed]...
MorphemeAddict@...
lojbaner
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Jun 5, 2006
5:34 pm
11745
In a message dated 6/5/2006 12:23:59 PM Central Standard Time, ... f(888)=1025 base 9 f(AA9)=1025 base 11 ... In general the highest f can be in a given base b...
MorphemeAddict@...
lojbaner
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Jun 5, 2006
5:52 pm
11746
Stevo, We've sure got a lot of time on our hands.:-) Some decimal solutions n,m n = 100a+10b+c such that m = n+a+b+c Notice the missing values of m eg.,...
cino hilliard
hillcino368
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Jun 5, 2006
7:55 pm
11747
In a message dated 6/5/2006 2:56:02 PM Central Standard Time, ... Only by hand, so the answer is no. stevo [Non-text portions of this message have been...
MorphemeAddict@...
lojbaner
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Jun 5, 2006
10:31 pm
11748
... post ... face ... are no ... particular, ... congruent ... (snip) ... By the various methods that you describe I find several numbers of identical pieces...
cooperpuzzles
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Jun 7, 2006
4:46 pm
11749
... randomly ... that x ... exactly ... M ... Or M = p1^9. 2^9=512 smaller than 976. 3^9=19683 too big. ... than...
cooperpuzzles
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Jun 7, 2006
5:07 pm
11750
... or ... Beautiful. That's a difficult exercise without actually making each ball. I think the one that dominates the page is an octahedron cut into sixes. ...
cooperpuzzles
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Jun 7, 2006
5:12 pm
11751
... You're perfectly correct; the rhombic dodecahedron has cubical (or octahedral) symmetry, but I missed it in my post because it arises by subdividing faces...
adh_math
Offline
Jun 8, 2006
2:30 pm
11752
... http://mathworld.wolfram.com/RhombicTriacontahedron.html...
adh_math
Offline
Jun 8, 2006
9:03 pm
11753
... but ... Good one. Also if the faces were not cut as mirror images, all the 3D pieces would also be identical; not half mirror images of the other half. ...
cooperpuzzles
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Jun 8, 2006
10:25 pm
11754
... but ... Good one. Also if the faces were not cut as mirror images, all the 3D pieces would also be identical; not half mirror images of the other half. ...
cooperpuzzles
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Jun 8, 2006
10:32 pm
11755
... When I saw this before I thought it was just a dodecahedron cut in fives; giving 60 pieces. Now I see that each triangle is joined to another forming 30...
cooperpuzzles
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Jun 8, 2006
10:49 pm
11756
... True, but then the result would be "polyhedral" only in two cases, when all the face-cutting rays pass through vertices, or through the edge midpoints. :) ...
adh_math
Offline
Jun 9, 2006
1:36 pm
11757
... Perhaps surprisingly, same for the cube. A rhombic dodecahedron has 6 vertices incident on 4 faces, and 8 vertices incident on 3 faces. Bisecting rhombic...
adh_math
Offline
Jun 9, 2006
2:32 pm
11758
If A, B and C are the angles of a triangle, r and R are respectively the inradius and circumradius of a triangle, then cos(A)+cos(B)+cos(C)=1+(r/R). This is an...
Joseph
aldimalkoun
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Jun 11, 2006
8:28 am
Messages 11729 - 11758 of 13927   Oldest  |  < Older  |  Newer >  |  Newest
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