EPTOnly the first statement is true. Just start from Statement 5 and work your way up from that.
small brain teaser... enjoy - Page 5
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iamke55
United States2806 Posts
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dyodyo
Philippines578 Posts
+ Show Spoiler + 1, 2 and 5 are true 3 and 4 are false | ||
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araav
Armenia1590 Posts
On August 19 2008 14:51 iamke55 wrote: + Show Spoiler + Only the first statement is true. Just start from Statement 5 and work your way up from that. true | ||
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iPF[Div]
Spain572 Posts
if s4 is true than s2 must be true, but statement 4 also states s3 is true while s2 states that it s false, which means impos. if s4 is false then s2 must be false but by making statement 4 false it would also state than s3 must be false while a false s2 would state s3 must be true, which means impos. ^this is done assuming that being false would completely reverse the statement, however being false doesn't necessarily mean that it is completely wrong, it is simply not wholly correct. which makes s1=t s2-s5=f a possible answer | ||
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Glider
United States1353 Posts
On August 19 2008 14:51 iamke55 wrote: + Show Spoiler + Only the first statement is true. Just start from Statement 5 and work your way up from that. what about... On August 19 2008 06:29 X.xDeMoNiCx.X wrote: try and figure out which statments are really true and which are really false.  enjoy...each true keeps the statement the same, each false reverses it. | ||
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Caller
Poland8075 Posts
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BottleAbuser
Korea (South)1888 Posts
Uhm... what? Maybe "tnemetats lacigol a" ? There is no such logical term as a "reverse." If you assign some arbitrary meaning to the word, such as a function that maps from "A AND B" to "NOT A AND NOT B," then yes, the system becomes unsolvable. It is much more reasonable to assume that the "reverse" of a statement is the negation of it. What is the "reverse" of "The sun is shining?" "The not-sun is not shining?" Or "The sun is not shining?" Come on, use common sense. "If the red light is on, don't go." "If the green light is on, go." How do you reverse those? "If the light that isn't red isn't on, go." "If the light that isn't green isn't on, don't go." Right? Jeeeeeez. Even more intuitive example: This statement is false: "I am 21 years old, and I have 10 million dollars." It is false because although I am 21 years old, I do not have 10 million dollars. Just because the statement is false doesn't mean that I'm not 21, though. Now, if we "reverse" that statement, we'll end up with "I am not 21 years old and I do not have 10 million dollars." Obviously, both the statement and its reverse are FALSE, and assuming that the two together cover all of the possibilities is fallacious. | ||
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Glider
United States1353 Posts
On August 19 2008 15:48 BottleAbuser wrote: Okay, what is a "reverse" of a logical statement? Uhm... what? Maybe "tnemetats lacigol a" ? There is no such logical term as a "reverse." If you assign some arbitrary meaning to the word, such as a function that maps from "A AND B" to "NOT A AND NOT B," then yes, the system becomes unsolvable. It is much more reasonable to assume that the "reverse" of a statement is the negation of it. What is the "reverse" of "The sun is shining?" "The not-sun is not shining?" Or "The sun is not shining?" Come on, use common sense. "If the red light is on, don't go." "If the green light is on, go." How do you reverse those? "If the light that isn't red isn't on, go." "If the light that isn't green isn't on, don't go." Right? Jeeeeeez. Even more intuitive example: This statement is false: "I am 21 years old, and I have 10 million dollars." It is false because although I am 21 years old, I do not have 10 million dollars. Just because the statement is false doesn't mean that I'm not 21, though. Now, if we "reverse" that statement, we'll end up with "I am not 21 years old and I do not have 10 million dollars." Obviously, both the statement and its reverse are FALSE, and assuming that the two together cover all of the possibilities is fallacious. where u get the if statements from, was that in the original questions? I take reverse as used in this case simply means flip true and false... the reverse of (A is true, B is false) is (A is false, B is true). I don't see how else to interpret him add "reverse the statement". Not to mention only first statement had "AND' in it, every other one is just a comma which confuses things further. And I already said it makes more sense for TFFFF since following commonsense a statement can be false if just one of its parameter is wrong. But a lot of logic questions and puzzles requires you to strictly follow the words, and in this case "Reverse" is not too clear. | ||
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BottleAbuser
Korea (South)1888 Posts
Statement 2 says that statement 1 is false, 3 is true. Truth table: 2 | 1 | 3 T | F | T F | F | F F | T | F F | T | T Those are the possibilities given by Statement 2. Logically equivalent to AND. Q.E.D. Also, if you're saying "reverse" means "break into atomic components and reverse each of those," then... well, that's not really a common way to interpret the word. What happens if you reverse a train? Do you turn the whole thing around, or the individual cars and re-link them, or maybe chop them into their constituent molecules and turn each one of those by 180 degrees on the XY plane? The interpretation where we take the whole thing and flip the sign (negation) makes the most sense to me. | ||
mikeymoo
Canada7170 Posts
+ Show Spoiler + Assume 1 is true.. 2 is false 3 is false 4 is false 5 is false. Assume 1 is false. Assume 2 is true 3 is true 4 is false 5 is true Assume 1 is false Assume 2 is false 3 is then not true, that would make 2 true. But 3 cannot be false, or 1 would be true. So I think my first two satisfy. | ||
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BottleAbuser
Korea (South)1888 Posts
On August 19 2008 14:15 mikeymoo wrote: + Show Spoiler + Assume 5 is true. 3 and 1 are then true. But 1 says 3 is false. So 5 must be false. 3 is then false. so 2 is then false. Then 4 is false. 1 is true. TFFFF I was referring to this post. You have a statement "5 must be false. 3 is then false." The second statement doesn't follow from the first - it would only if you also had such a statement like "3 is false if 5 is false," which we don't. Probably you omitted some steps, and the conclusion isn't wrong, but the reasoning is incomplete. Also, in your more recent post, you seem to say that 5 can be true, but it can't - 5 being true leads to contradiction. | ||
Pholon
Netherlands6142 Posts
Nope, is 2 is TRUE, 3 must be TRUE as well On August 19 2008 10:58 sYz-Adrenaline wrote: + Show Spoiler + statement 1) 2 and 3 are false. statement 2) 1 is false, 3 is true. statement 3) 4 is false, 5 is true. statement 4) 2 is true, 3 is false. statement 5) 1 is true, 3 is true. statement 1) = OK statement 2) = OK statement 3) = OK statement 4) = 3 reverses to true! 2 stays the same false statement 5) = 3 stays the same and so does 1. 1 F 2 F 3 T 4 F 5 T Ez Check PLz ?On August 19 2008 13:16 sYz-Adrenaline wrote: F F T F T Nope, cause if 5 is TRUE then 1 is TRUE also | ||
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Elite]v[arine
United States264 Posts
whatever =( | ||
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Raithed
China7078 Posts
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Pholon
Netherlands6142 Posts
On August 19 2008 19:26 X.xDeMoNiCx.X wrote: im satisfied that my friend gave me an unsolvable problem. from what i read here.... whatever =(Hey, you promised to post the answer later on =/ | ||
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opsayo
591 Posts
If something is true, then both of its arguments hold. If something is false, then both of its arguments are false, i.e. the opposite is what is actual. If he means that only one or the two arguments can be false i.e.: ex: Cats are animals and Plants are animals - a false statement despite one of its premises being true... then I don't really feel like solving it which others have figured out. | ||
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sYz-Adrenaline
United States1850 Posts
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orca
Israel469 Posts
reverse means NOT. example: statement 2 (1 is false, 3 is true) is false, reverse it: => NOT ( 1 false AND 3 true) => NOT(1 false) OR NOT(3 true) => 1 true OR 3 false. edit: oh and TFFFF works. | ||
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Ryan307 :)
United States1289 Posts
that outta stir some shit up? | ||
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AcrossFiveJulys
United States3612 Posts
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