Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

There is a box in which distinct numbered balls have been kept. You have to pick two balls randomly from the lot.

If someone is offering you a 2 to 1 odds that the numbers will be relatively prime, for example
If the balls you picked had the numbers 6 and 13, you lose $1.
If the balls you picked had the numbers 5 and 25, you win $2.

Will you accept that bet?

An inspection by the superintendent of St. Joseph School was scheduled on the next day. The class teacher Jenifer knew that he would be asking questions from her class and she would have to choose a pupil to answer. To offer a perfect impression over him, the teacher explained certain instructions to the students to maximise the chances of getting correct answer every time.

What did she say to the students?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

You see me once in June, twice in November, and not at all in May. What am I?

Can you find out the remainder when 3^300 is divided by 5?

I make two people out of one. What am I?

Can you spot the man between the coffee bean in the picture below ?

You are a cab driver who pools passengers. You pick 3 people from a destination and drop 1 after an hour. 2 people climb aboard at the same time and you drop 3 at the next destination. After some time, you pick 2 passengers only to drop 1 after a short distance where 3 more passengers climb up the cab. You leave the rest of the passengers one by one to their destination and then come back home.

Can you tell the eye color of the cab driver?