Question

Five students are seated in a circle. Each student has either a red disc or a green disc painted on

Answer 1

Answer:

Students 3 and 4 have green discs.  Students 1, 2, and 5 have red discs.

Step-by-step explanation:

If Student 1 is telling the truth, Students 2 and 3 must be lying.  If that were true, Student 1 would see at least 2 red discs, not 1.  So Student 1 is lying, and therefore has a red disc.

Therefore, Student 5 is also lying, and must also have a red disc.

If Student 2 is telling the truth, the other four students must be lying.  That means Student 2 would have a green disc, and the other four would have red discs.  But if that were true, then Student 3 would be telling the truth.  Therefore, Student 2 is lying.

So far, we know Students 1, 2, and 5 are lying.  If Student 3 is telling the truth, then she and Student 4 each have a green disc.  If Student 3 is lying, then all five students would have red discs, which would mean Student 2 was telling the truth.

Therefore, Students 3 and 4 have green discs.  Students 1, 2, and 5 have red discs.