I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

Can you replace the question mark with the correct number?

Begin with a word, five letters to my name,
Remove the first and last but I am the same
Take out my middle and still, I remain.
What word am I?

Complete the following series. It.s very logical:

1, 4, 5, 6, 7, 9, 11, __?

Can you write down eight eights so that they add up to one thousand?

If you were to put a coin into an empty bottle and then insert a cork into the neck, how could you remove the coin without taking out the cork or breaking the bottle?

Can you find the missing piece of the Porsche?

Considering the below equation:

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?

I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?

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