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.

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

Count the number of triangles in the below picture?

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

What is greater than gold but cannot be bought. it can never be sold and can earn if its sought. though it can be broken, it can still be fixed. for by birth it can't start nor by death it is ended.what am i?

Without looking at a calendar, within a minute name, a boy's name using 5 consecutive 1st letters of 5 consecutive months

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

A four-digit number (not beginning with 0) can be represented by ABCD. There is one number such that ABCD=A^B*C^D, where A^B means A raised to the B power. Can you find it?