I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

As you can see that fifteen matches have been used to form an arrangement. What you have to do is remove any six of them to make them ten.

What kind of band never plays music?

Buy me, smell me or deliver me, I do not change.

Who am I?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

You’ll find me on Mercury, Earth, Mars, Jupiter, Saturn, and Uranus. But never Neptune, or Venus. What am I?

A bridge is about to collapse. There are four people P, Q, R and S on one of the sides. Before the bridge collapses, they want to cross it. Now since the bridge is too weak, it can only stand the weight of two people at a time. Also, it is night time and nothing is visible. They have just one torch with them.

Now P takes one minute to cross the bridge, Q takes two minutes to cross, R takes five minutes to cross and S takes ten minutes to cross.

The bridge will collapse in seventeen minutes. How will they be able to cross the bridge before it collapses?

What has a ring but no finger?

How many letters are in the alphabet?

What goes up but never comes down?