How is the moon similar to a dollar?

Twice ten are six of us,

Six are but three of us,

Nine are but four of us;

What can we possibly be?

Would you know more of us?

Twelve are but six of us,

Five are but four, do you see?

What are we?

What number divided by 4 is the same as that number minus 4?

For an extra income, John decided to work at a Hotel for one hour daily. The manager offers him that they will pay him $11 after every 11 days.
However, John offered a different proposition to the manager. The offers stand as:
He will be paid just a penny on his first day.
Two pence will be paid on the second day,
Four pence will be paid on the third day.
And so on till the 11th day.

Should the Hotel manager accept his offer?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

What can you hold in your right hand, but never in your left hand?

John was piloting a plane behind a car but was never able to overtake it. Why?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?

Why do Chinese men eat more rice than Japanese men do ?