I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

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

After undergoing a successful eye operation, A blind girl has just boarded a train to her home. The doctor asked her to open the bandages after 3 hours. On her train journey, she opened the bandages and within a fraction of the time she commits suicide by jumping off the train.

Though her operation was successful, Why did she commit suicide?

A doctor and a boy were fishing. The boy was the doctor’s son, but the doctor was not the boy’s father. Who was the doctor?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

Ten coins have been arranged as you can see in the given picture. In this arrangement, a triangle is formed pointing upwards. You have to invert the position of the triangle and make it point downwards while changing the position of 3 coins only. Can you do it?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

I have two coins.
* One of the coins is a faulty coin having a tail on both sides of it.
* The other coin is a perfect coin (heads on side and tail on other).

I blindfold myself and pick a coin and put the coin on the table. The face of the coin towards the sky is the tail.

What is the probability that another side is also tail?