What is the fastest way to double your money?

Find The Missing Number In the Sequence.
6 25 64 ? 32 1

Rectify the following equality 101 - 102 = 1 by moving just one digit.

Find the Odd One Out?
84129
32418
47632
36119
67626
72927

A man is found dead in his bathroom naked with blood scattered all around him. The bathroom was locked from the inside and there is no trace of any struggle. There is nothing in the bathroom except his pant with the belt still around and his shirt. Also, the medic team can't find any incision in his body that may have been the reason behind so much blood loss.

The Police department is clueless regarding this murder mystery.
Can you?

There was an aeroplane crash, every single person died, but two people survived. How is this possible?

Manish and Manoj play 5 games of chess.
Both Manish and Manoj win the exact same number of games. There is no tie at all.

How?

Alex is stranded on an island covered in forest.
One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process.

There are cliffs around the island, so he cannot jump off.

How can the Alex survive the fire? (There are no buckets or any other means to put out the fire)

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?