I bet you will not know which card it is necessary to turn to solve this puzzle?

A lot of people like to play cards or show a card trick. And Site offers to try their hand at solving card puzzles that will test your ability to think logically. Take a look at the 4 cards that are pictured. You need to flip the card to check the correctness statement: if the card on the front side shows an even number, then its reverse side is blue. What cards need to be flipped to check whether it is true is this statement?

Seventy eight million six hundred eighty six thousand six hundred fourteen


There just need to explain what is the point:

  • Since the condition says nothing about odd numbers, then the card with the number 5 is not to be touched.
  • Also no need to flip the blue card. In this lies the catch. Cards with an even number must be a blue shirt, but that this statement works in reverse you can not immediately guess. That is, the blue card can be both even and odd number. Therefore, the blue card is not touched.
  • Card with eight flip need in any case to check whether it is blue.
  • If you turn the green card, and there will be an odd number, the condition still will not be broken, but if even, it will be. It turns out that the green card has to be flipped in any case.
So the answer:

Three million three hundred eighteen thousand seven hundred two

To check the validity of the claim that the odd card is the reverse side of the blue, you need to flip 2 cards: with a figure 8 and a green shirt.

via factroom.ru


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