Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

Find the next number in the sequence

5 12 24 36 ?

I am a five-letter word and people eat me. If you remove the first letter I become an energy form. If you remove the first two letters, I am needed to live. Scramble the last three letters and I am a drink. What word am I?

We have two identical balls in terms of diameter and weight. However, one of them is solid and the other is hollow.

Without knocking the ball, can you find the solid ball?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

Jack was having a candle light dinner with his girlfriend. Suddenly a cold gush of wind entered through the open window and three of the ten candles were extinguished. Assuming that none of the other candles were extinguished.

How many candles are they left with in the end ?

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?

How can you drop a raw egg from a height onto a concrete floor without cracking it?