Who always enjoys poor health?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

Why is a river so rich ?

If you say my name, I will no longer exist. What am I?

If a wheel has 54 spokes, how many spaces are there between the spokes?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

Can you find the odd one out from the below words ?

First Second Third Forth Fifth Sixth Seventh, Eighth Nine Ten Eleven Twelve.

Prove that the below maths equation is true.

8 + 8 = 91