People put me on the table and cut me but do not eat me. What am I?

I have two sand hourglasses:
1. A 7 minute one and
2. An 11-minute one.

Using just these 2 sand hourglasses, how can I measure time as 15 minutes?

If 1+9+8=1, what is 2+8+9?

There are two dice with empty faces in front of you and a marker. You can mark any number on each of the faces of the two dice, but you have to display all 31 days of the month using the two of them.

Which numbers will you mark on which dice so that you can easily depict all the dates of the month?

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 does this rebus picture means ?

What Adam and Eve do not have but the rest of the people have?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

In which direction should the missing arrow point?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?