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

O T T F F S S ?

What is the fastest way to double your money?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

On a bus, there is a 26-year-old pregnant lady.
A 30-year-old policeman.
A 52-year-old random woman.
And the 65-year-old driver.

Who is the youngest?

If two fifty-foot ropes are suspended from a forty-foot ceiling that is twenty feet apart, how much rope will you be able to steal if you have a knife?

The dirtier I get, the whiter I look. Who am I?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?