This is not too taxing and is my first puzzle, so go easy on me!
There are four cards on the table with faces showing either a letter or a number:
B D 3 7
Given that each card has a letter on one side and a number on the other, which 2 cards would you need to turn over to prove the statement that all cards with a B face have a 3 on the other side?
Maybe not what you first think: You need to turn the B card and the 7 card.
You need to turn the B card to check that there's a number 3 on the other side. The D card proves nothing. It doesn't matter what's on the reverse of the 3 card - the statement only says that a B card has a 3 on the other side NOT that a 3 must have a B on the other side. Turning the 7 card as well as the B card proves the statement one way or the other - if there's a B on the reverse of the 7 card then the statement will be proved to be wrong, otherwise it's true.
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Hello
This is not too taxing and is my first puzzle, so go easy on me!
There are four cards on the table with faces showing either a letter or a number:
B D 3 7
Given that each card has a letter on one side and a number on the other, which 2 cards would you need to turn over to prove the statement that all cards with a B face have a 3 on the other side?
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