Logical problem from Kangaroo

Hey Brilliant, Yesterday I was ansering a logical problem from Kangaroo. It tells that there are 25 people colocated in file and there are some which always tell the truth and some who always lied. Then it tells what one people say and you have to verifie if he tells true or tells false and then you take your own conclusions. Finally I got the problem but I did it by trial and error because I had a doubt. The point is: If somebody tells for example:

-All the people in the file lie.

By comparing what happens if this is true I verified this "somebody" says wrong and there arrives the problem. If this sentence is wrong this means that:

All the people says true.?
Not all the people says false.?

Thanks in advance.

#HelpMe! #Opinions

Easy Math Editor

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Comments

It clearly means that All the people do not say lie or in other words "Not all people say false."

Rahul Nahata - 7 years, 10 months ago

Thanks!

Jordi Bosch - 7 years, 10 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$