Brain Teasers
Aliens on Earth
100 aliens attended an intergalactic meeting on earth.
73 had two heads,
28 had three eyes,
21 had four arms,
12 had two heads and three eyes,
9 had three eyes and four arms,
8 had two heads and four arms,
3 had all three unusual features.
How many aliens had none of these unusual features?
73 had two heads,
28 had three eyes,
21 had four arms,
12 had two heads and three eyes,
9 had three eyes and four arms,
8 had two heads and four arms,
3 had all three unusual features.
How many aliens had none of these unusual features?
Answer
4 aliens.Draw a venn diagram.
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I got 27. How did you get the answer 4?
its pretty complicated
Apr 16, 2006
I got 7 the first time but after seeing the answer I figured out where I went wrong
Nice set and su-set puzzle.
Nice set and SUB-set puzzle.
It was interesting to read, but I have to admit I did not reach the desired answer. Would love to see an explanation added to that for more information and clarity if you could!
You guys know how to draw venn diagrams??(you know the interconnecting circles) because thats how you solve this... I got 4 on my first try.
56 had only two heads
10 had only three eyes
7 had only 4 arms
9 had only two heads and three eyes
5 had only two heads and four arms
6 had only three eyes and four arms
3 had three eyes, four arms, and two heads.
if you draw the venn diagram its very easy
56 had only two heads
10 had only three eyes
7 had only 4 arms
9 had only two heads and three eyes
5 had only two heads and four arms
6 had only three eyes and four arms
3 had three eyes, four arms, and two heads.
if you draw the venn diagram its very easy
Quite fun, but I didn't need to draw ven diagrams to solve this, it's just like the total area of three intersecting circles (C1 , C2 , C3). It's the sum of all areas minus the sum of all binary intersections plus the little area where all circles intersect.
In this case it was 73 + 28 + 21 - 12 - 9 -8 + 3 = 96 alien with unusual features, leaving only 4 aliens without any of these features. lol
In this case it was 73 + 28 + 21 - 12 - 9 -8 + 3 = 96 alien with unusual features, leaving only 4 aliens without any of these features. lol
AWESOME!!! Woot!
did you doublecount something? better sub it out.
i liked it
OK, the unusual features are two heads, three eyes, and four arms. On each line of the puzzle, if a feature is NOT mentioned, that line has no comment about that feature being present or not.
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