Three Of The Best Puzzle - Solution
The Puzzle:

Professor Frantic set these three problems to her class of maniacs at Clueless University.

Three replies are given below:

If everybody got one question wrong, what are the correct answers to Professor Frantic's questions?

Three replies are given below:

If everybody got one question wrong, what are the correct answers to Professor Frantic's questions?
Our Solution:
It may seem obvious, but if everybody got one question wrong, then everybody got two questions right! Have another look at the answers:
If the first person got Question 1 wrong, then so did the second person.
That gives two completely different sets of "correct" answers for Question 2 and Question 3!
So Person 1 Question 1 must be right: "TWO".
The same working gives the other answers.
So Q1 TWO, Q2 THREE, Q3 TWO are the correct answers.
If the first person got Question 1 wrong, then so did the second person.
That gives two completely different sets of "correct" answers for Question 2 and Question 3!
So Person 1 Question 1 must be right: "TWO".
The same working gives the other answers.
So Q1 TWO, Q2 THREE, Q3 TWO are the correct answers.
Puzzle Author: Stephen Froggatt
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