Find the value of "?" in the ball picture Riddle below:

What is the word or phrase?

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

Can you find out the missing number in the grid?

A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?

I’m tall when I’m young, and I’m short when I’m old. What am I?

Can you discover the missing number in this series?

37, 10, 82
29, 11, 47
96, 15, 87
42, ?, 15

What came first, the chicken or the egg?

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?

What's the only room from which no one can enter or leave