Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

A red house is made out of red bricks. A yellow house is made out of yellow bricks. And, a blue house is made out of blue bricks. So, what is a greenhouse made of?

What have one eye but still cannot see?

What can you serve, but never eat?

I organized a small get together at my home.
In the party , i have a barrel with some whiskey in it.

Suddenly Guest 1 say 'I bet this barrel of whiskey is more than half full'.
'No, it's less than half full' Guest 2 replied.

I don't have any measuring instrument and without removing whiskey from it , how can i determine which of the guest is right ?

What does this mathematical rebus means ?

What is so fragile that saying its name breaks it?

Can you replace the question mark with the correct letter?

6 + 6 + 6 = N
7 + 7 + 7 = E
8 + 8 + 8 = R
0 + 0 + 0 = ?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

People make me, save me, change me, raise me. What am I?