Best riddles with simple answers

What does this rebus say? XLR8.

What has no beginning, end, or middle?

I weigh almost nothing. I am lighter than air. But even the strongest man in the world cannot lift me. What Am I?

Had at work day and night, it counts the numbers over and over. Although it counts all its life, it never gets past twelve.

It's red, blue, purple and green. No one can reach it, not even the queen.

Think of a number. Double it. Add ten. Half it. Take away the number you started with. What is your number?

What kinds of stones are never found in the ocean?

If you drop a yellow hat in the Red Sea, what does it become?

Whats a sheep's favorite game?

When you do know me about me, them I am definitely something. You will always search for me. But when you know me, I am nothing. Who am I?