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?

Count the number of triangles in the given picture.

My location can be determined by the below rebus.
So where am i ?

Rob is taller than Edwin, and Jurgen is shorter than Rob.
Of only one of the following statements, we now certainly know it is correct:

A.Edwin is taller than Jurgen
B.Jurgen is taller than Edwin
C.It cannot be determined if Jurgen or Edwin is the tallest.

A Shopkeeper collects 71 rupees in the form of 20 paisa and 25 paisa.
He collects a total of 324 coins.

Can you tell me how many number of 20-paisa and 25-paisa he got?

Can you solve below mathematical equation?

2^1234 - 2^1233

John went to a parrot shop in Mexico, and the parrot owner told him that his parrot is so unique that he repeats everything he hears. John got excited and immediately bought the parrot. John went home and spoke many words, but the parrot does not repeat anything.
He went again to the parrot shop and complaint to the shopkeeper, but the shopkeeper never lied. Explain?

What number do you get when you multiply all of the numbers on a telephone's number pad?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

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 ?