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

Buy me, smell me or deliver me, I do not change.

Who am I?

Can you write down eight eights so that they add up to one thousand?

I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

What does the below rebus puzzle mean?

John gave half of the apples he had plus one more to Jacob. He gave half of the remaining ones plus one more to James. Now, John was left with just one apple.

Can you find out how many did he have in the beginning?

The captain of a ship was telling this interesting story: "We travelled the sea far and wide. At one time, two of my sailors were standing on opposite sides of the ship. One was looking west and the other one east. And at the same time, they could see each other clearly." How can that be possible?

Can you name some countries which do not have the alphabet 'A' in them?

What animal walks on four legs in the morning, two legs during the day, and three legs in the evening?

Oedipus, the king of Thebes, figured out the answer to the riddle:

In front of you, there are 9 coins. They all look absolutely identical, but one of the coins is fake. However, you know that the fake coin is lighter than the rest, and in front of you is a balance scale. What is the least number of weightings you can use to find the counterfeit coin?