I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

2 ladies and 2 girls need to cross a river in a boat big enough for 1 LADY or 2 girls. How do they do it?

If you go to the movies and you're paying, is it cheaper to take one friend to the movies twice, or two friends to the movies at the same time?

Complete the table series riddle by finding the number that can replace "??".

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?

I am the fastest animal but cannot climb the tree. What am I?

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?