What has many keys but can’t open a single lock?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

What is common among 11, 69, and 88?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Find the next number in the series below.

6 18 270 72090 ?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

A man hijacks an aeroplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?

Your mother’s brother’s only brother-in-law is asleep on your couch. Who is asleep on your couch?