Cristina was born in 1888. She just had her 30th birthday today how did that happen?

Can you place six matchsticks in a manner that each of the matchsticks is in touch with the other five matchsticks?

Remove two matchsticks to make the below equation correct.

what does the below rebus mean?

You have two bottles of pills marked with labels A and B. The pills are identical. The doctor has asked you to take one A pill and one B pill daily. You cant take more or less than that.

While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.

You cant throw away the expensive pills. What will you do now?

what does the below rebus means?

If eleven plus two equals one, what does nine plus five equal?

If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

Can you find out the number that should replace the question mark with a valid reason?

You are trapped in a room with two doors. One leads to certain death and the other leads to freedom. You don't know which is which.
There are two robots guarding the doors. They will let you choose one door but upon doing so you must go through it.
You can, however, ask one robot one question. The problem is one robot always tells the truth, the other always lies and you don't know which is which.
What is the question you ask?