It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

If you drop a 15 kg iron bar and a 5 kg bag of cotton from a height of 50 meters which will reach the ground first?

If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?

You have a basket containing ten apples. You have ten friends, who each desire an apple. You give each of your friends one apple.
Now all your friends have one apple each, yet there is an apple remaining in the basket.
How?

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

What is black when you buy it, red when you use it, and gray when you throw it away?

What do you call a fish without an eye?

What question can you never answer yes to?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

If 1+9+8=1, what is 2+8+9?