collatz conjecture

1st April is a day of fun, humor and enjoyment. Even though, I have lot of fun puzzles on this blog, these ten are totally meant for today. Enjoy!


1. If you are in a dark room with a candle, a wood stove and a gas lamp. You only have one matchstick in the matchbox, so what do you light first?

2. If the question you answered before you answered the question you answered after you answered the question you answered before you answered this one, was harder than the question you answered after you answered the question you answered before you answered this one, was the question you answered before you answered this one harder than this one? YES or NO?

3. There are 10 lit candles on a table. A strong breeze comes and extinguishes 2 of the candles. When you come back later, you see that 1 more has been blown out.To make sure no more flames go out, you shut the window. Assuming the wind doesn’t extinguish any more candles and you don’t relight the extinguished candles, how many candles do you have left in the end?    (Source)

4. Paper is white. Cotton is also white. White-board is white. Clouds are white. Eggs are white. Flour is white. Rice is white. Milk is white. Some cows are white. Now tell me, what does a cow drink?

5. How much is 4090 and 10 ?

6. You arrange five coins on a table in a way such that two coins are on one side and two are on the other. The fifth one is placed exactly at the center. Your son asks for a coin and you give him the middle one. How many coins are left?

7. I was riding a horse. There was a fire engine just next to me. A helicopter was following me. To the left there was a sports car moving and to the right hand there was a depth. I managed to stop all of them at a sudden, without crashing and without communicating to the respective pilots. Guess, how??

8. What to put in a tank of water which will make it lighter?

9. What are the four days which start with a ‘T’?

10. Who manages the time?



Answer of Puzzle 1

The Matchbox.

Answer of Puzzle 2


Answer of Puzzle 3

Three (3).

Answer of Puzzle 4

Water. (Did you think about milk?)

Answer of Puzzle 5

4100. (Did you think 5000?)

Answer of Puzzle 6

Two. (Not four!)

Answer of Puzzle 7

I was on Merry-Go round.

Answer of Puzzle 8

A hole.

Answer of Puzzle 9

Tuesday, Thursday, Today and Tomorrow.

Answer of Puzzle 10

Nancy Gibbs, the Managing Director of Time.

Answer of Puzzle 11

Happy April Fools’ day, idiot! 😉

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