A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

How old is your son? asked a man to his neighbour. My son is five times as old as my daughter and my wife is five times as old as my son. I am twice as old as my wife whereas my grandmother, who is celebrating her eighty-first birthday is as old as all of us put together.

How old is the man's son ?

Highly detail-oriented individuals excel at this type of optical illusion challenge. It requires not just good eyesight but also the ability to distinguish subtle differences quickly. Finding the 6 among all these 9's could indicate a high level of IQ and superior observational skills.

Spot what is wrong here in below Picture?

I shave every day, but my beard stays the same. What am I?

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?

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

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

Can you arrange the six given marbles in a manner that each one of them is touching all four marbles of different colours?