I am a prime number.
The double of myself is equal to the square of me.

which number am I?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

Before Mount Everest was discovered, what was the highest mountain in the world?

How many triangles can you count in the figure given?

What is the next number in this matchsticks series riddle?

John: "Hi Teacher, What is your favourite movie ?".
Chemistry Teacher: "Indium Cerium Platinum Iodine Oxygen Nitrogen".
Ten seconds later... John replied I got it.

Do you?

Can you identify the hidden rebus in the image below?

I can be cracked, made, told, and played. What am I?

What four weights can be used to balance from 1 to 30 pounds?