Puzzle 12 : Cards, cards

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 Solution to puzzle 11:

The monk will light both ends of one incense stick and one end of second incense stick.

By 30 minutes, first stick will completely burn out and second stick will burn out half. Now the monk will light the other end of second stick. Now the second stick will burn in half the time of 30 minutes. That is, it will burn out in another 15 minutes. 

By the times both sticks burn out, it will be 45 minutes.

Puzzle 12 : Cards, cards

This puzzle is from readers digest.

A small number of cards has been lost from a complete pack. If I deal among four people, three cards remain. If I deal among three people, two remain and if I deal among five people, two cards remain. How many cards are there?

Guessing game 

Before I close this post, I will show you a guessing game.

Guess any number. Now double the number. Add 10 to it. Next halve the number. Subtract original number from it. Now your answer is 5. Is it not?

 So, how do people do that?

Simple. 

Let us say original number was x.

  1. When you double it, it is 2x
  2. Add 10 to it - 2x+10
  3. Halve it - (2x+10)/2 - x+5
  4. Now subtract original number from it. - x+5 - x = 5

You can frame your own question in similar lines. Won't you?

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