Good Riddles

Question: I can fly in your mind. I was not made to scare anyone, but many fear me. What am I?

Question: How many times can you subtract 10 from 100?

Question: Which runs faster, hot or cold water?

Question: You are a junior detective investigating a case. Boys at an apartment complain that every day, they have an egg-spinning competition with only raw eggs, and every day one particular boy wins. The boys want you to find out how. You are observing the boy spinning an egg when suddenly it drops to the floor. The apartment clerk casually hands him a broom to clean it up, as if it happens every day. You now know why the boy always wins the daily competition. How?

Question: I am a teacher, yet I am not a human nor a robot.