There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

If two's company, and three's a crowd, then whats four and five ?

By moving just one matchstick, you need to make the below statement true. Can you do it?

In which direction should the missing arrow point?

Find the next number in the sequence

1, 2, 6, 21, 88, __?

An equation has been laid down using a few matchsticks. However, as you can see, the equation is not correct. Can you correct the equation if you are allowed to add or remove 5 matchsticks?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

Count the Triangle in the figure given below:

I am something people love or hate. I change peoples appearances and thoughts. If a person takes care of them self I will go up even higher. To some people I will fool them. To others I am a mystery. Some people might want to try and hide me but I will show. No matter how hard people try I will Never go down. What am I?