Good Riddles

Question: There are 4 light bulbs in a room and 4 switches corresponding to these four light bulbs (in a random order). You cannot see the light bulbs from where the switches are.

If you can only visit the room with the light bulbs once, how can you figure out which switch belongs to which light bulb?

Question: Does an ounce of gold or an ounce of feathers weight more?

Question: I am a big threat to humanity,
but you wouldn't get rid of me even if you could.

What am I?

Question: At the end of a long dark cave there is a monster made of lead. Be careful. One twitch of the finger and you will release it.

What is it?

Question: How high would you have to count before you use the letter 'A' in the spelling of a number?