Brain Teasers
Four Girls
A man escapes from jail with help from his girlfriend. Four girls are accused of being the man's girlfriend. His girlfriend is lying. Two girls are innocent and telling the truth. The other girl is the man's sister who is helping the girlfriend lie. Who is the man's sister?
Amanda: "Melinda is his girlfriend."
Vanessa: "Eva is lying."
Eva: "Amanda is lying."
Melinda: "Vanessa is not his sister."
Amanda: "Melinda is his girlfriend."
Vanessa: "Eva is lying."
Eva: "Amanda is lying."
Melinda: "Vanessa is not his sister."
Answer
If Amanda is telling the truth, then Melinda is lying. If Melinda is lying, then Vanessa is his sister. If Vanessa is his sister, then she's lying about Eva lying. If Eva isn't lying, then Amanda is lying, which would contradict the fact that Amanda's telling the truth. That means Amanda is lying and could be his girlfriend or sister.Eva must be telling the truth since Amanda has to be lying. So Vanessa must also be lying, and Melinda is telling the truth. Since Melinda's telling the truth, Vanessa isn't his sister and must be his girlfriend. Amanda is the other liar, so she must be his sister.
Answer: Amanda
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Comments
Great teaser
I liked this one - and I figured it out, too.
it was very confusing but i thought it was really fun and cool
great plot !! takes some time to figure out
now who'll get in the prison sister or the girl friend?
now who'll get in the prison sister or the girl friend?
Wait. So. HUH?
good teaser, I realy liked it
WOW!!! Somehow I did figure it out (the same way you did) but even knowing that, I'm still like "Huh?"
Easy!
I liked how you really have to put your mind to it too sort everything out, great teaser!
Fantastic! I'm so confused that I don't remember if I got it right or not, but I had fun either way! Good job!
That was really confusing. lol
Very easy with a little thinking.
The only thing I know for sure is I didn't get it right Great teaser. Thanks for posting.
I usually get these with the help of pen and paper and enjoy them. This one is no exception.
Nothin' like a logic matrix to help you work through these! Fun teaser.
Wow. I don't know if the explanation helped or hindered, but I got it right! I'd like to see the symbolic logic diagram behind that. Alas. Braingle is text only.
I got it right. The explain kind confuses me though.
TGIF!!!... i would probably never got that right if it were a Monday morning!!! ... Great teaser, though i explained it to my oldest daughter in a lot less words than you did!!!
Very fun and confusing.
My mom's gonna LOVE this one!!
My mom's gonna LOVE this one!!
Best teaser ever. I love these sorts of logic puzzles where you have to work out who's lying. I worked it out with weird symbols so I'm don't follow your explanation, but I got to the same answer. This is in my favourites list.
One small thing - you said that the sister is helping the GF lie, but you never said outright that the sister is lying herself. I had to make that assumption.
One small thing - you said that the sister is helping the GF lie, but you never said outright that the sister is lying herself. I had to make that assumption.
Seems to me this also works w/ Vanessa the girlfriend and Amanda the sister.
Amanda's lying, therefore Melinda isn't the GF (check)
Vanessa's lying, therefore Eva's telling the truth when she says that Amanda's lying (check)
Eva's telling the truth that Amanda's lying (because she's the sister)
Melinda is telling the truth about Vanessa not being the sister, because she's the girlfriend.
Amanda's lying, therefore Melinda isn't the GF (check)
Vanessa's lying, therefore Eva's telling the truth when she says that Amanda's lying (check)
Eva's telling the truth that Amanda's lying (because she's the sister)
Melinda is telling the truth about Vanessa not being the sister, because she's the girlfriend.
nice!
oops please disregard the previous comment...i was thinking the question was asking for the girlfriend, since, according to the story, she's the one to be accused
This teaser was hard!!! I was so confused that I totally gave up be4 even trying!! It was really fun, though! Keep making those kinds of teasers!!
I loved this teaser
I can NEVER get these... Good Teaser.
It took awhile, but I figured it out. But who would want to be the girlfriend of a jailbird?
funny!
I do not even try to figure these out. They give me a headache. Only kidding, but I do not take the time to do them. Glad you all liked them and some of you figured them out. Good for you! More patience than I have.
These type of teasers are great but I never do too well on them. Impatient, I guess.
Also, am glad to see it got at least one other comment - on rerun - other than my own.
Thank you, Babe.
LGM
(WHY .. WHY .. is he laughing?)
Also, am glad to see it got at least one other comment - on rerun - other than my own.
Thank you, Babe.
LGM
(WHY .. WHY .. is he laughing?)
OK I confess, I am not a logical person. Even the answer has me completely confused.
I thank you CM ... on behalf of Carlos16 who departed these pages over five years ago.
He would, I'm sure, have appreciated your taking the time to read his contribution and to make a comment.
LGM
(still laughing !!)
He would, I'm sure, have appreciated your taking the time to read his contribution and to make a comment.
LGM
(still laughing !!)
Fun teaser, but omg tried are for B B 02!
Tricks are for B b02
Fun, easy and entertaining teaser; I got it right away.
I had quite a bit of fun working this one out. Excellent teaser!
I'm with Babe on this one. I guess we all have our puzzles that try our patience. The answer REALLY confused me! I wanted to see how to get to the answer and was lost!
Very nice.
A suggestion about wording: the puzzle says that the sister is "helping the sister lie". I assumed (correctly) that this means she is also lying, but conceivably she could help the girlfriend by telling the truth or creating a paradox or something? The logic would out of my league and I thought the setter wouldn't be so diabolical, but who knows?
A suggestion about wording: the puzzle says that the sister is "helping the sister lie". I assumed (correctly) that this means she is also lying, but conceivably she could help the girlfriend by telling the truth or creating a paradox or something? The logic would out of my league and I thought the setter wouldn't be so diabolical, but who knows?
Correction "helping the girlfriend"
I like this teaser-fun and I also got it.
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