There is no such number. Since the question says, after shuffling, “the new number” becomes double the original, it implies that the number, if exists, MUST be a two-digit number. (Otherwise, when you shuffle digits, you will get multiple new numbers. E.g. consider the number 124. Shuffling the digits, we get 142, 214, 241, 412, and 421.) So, we can’t say “the new number” is so-and-so. It can only be “one of the new numbers”. “The new number” is possible only if it is a two-digit number, so that ‘shuffling’ gives only one new number.)

And, among the two-digit numbers, there is no such number that, when digits are reversed, results in doubling the number. The closest you can get is with 37, which, when shuffled, becomes 73, which is 1.973 times the original.

4 Pounds.

The original composition was 90% liquid + 10% solid. The total was 20 Pounds. That means the mixture was composed of 18 Ponds liquid and 2 Pounds solid. (90%-10%)

After evaporation, the solid part will remain 2 Pounds, but the liquid is reduced to some ‘X’ pounds. However, this quantity is found to be 50% of the mixture. i.e., the 2 Pound solid part makes the other 50%. Hence, the total weight of the mixture must be 4 Pounds.

“John and Jacob play 5 games of chess” — Not necessarily against each other! It is possible that each of them played 5 games each against some other players, in which both won same number of games.  (All five games need not be against other players. It can be 4 games with each other, in which both won two each, and both won their respective fifth games (against some other player).

There are no prisons anywhere in the world that could hold Irene, the cyclone, behind the bars!

John is the King, Jacob, the Spy and Jonny is the bureaucrat.

1. If John was not the King:

Either Jacob OR Jonny must be the King. However: If Jacob was the King, he must tell the truth, whereas he said that John is the King which is wrong as per assumption. Similarly, if Jonny was the King, he wouldn’t have claimed to be a Spy.  Hence, John MUST be the King.

Now, what remain to be determined is who among Jacob and  Jonny is a Spy / Bureaucrat

2. If Jacob was the Bureaucrat (who is a liar):

He wouldn’t have made the statement “John is a king” which is true. Hence, Jacob must be the Spy.

From the above, it follows that Jonny, the only person remaining, must be the bureaucrat.

Periodic Table

RED in the FACE / RED-FACED

2^1233

Well, I think it’s not “three-fifths chick two third cat”, but ‘four-fifths CHICk’ and  one-third cAt’…! The ‘GOat part’ is ok…!! 🙂