What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

I am white when I am dirty, and black when I am clean. What am I?

There is an exact a week gap between Christmas and New Year. Hence, It is obvious that the new year that comes right after Christmas comes on the same day of the week.

A Strange thing happened in the Year 1777. Christmas occurs on Wednesday and New Year on Monday. How is that possible?

Can you place six matchsticks in a manner that each of the matchsticks is in touch with the other five matchsticks?

I have a big mouth and I am also quite loud! I am NOT a gossip but I do get involved with everyone's dirty business.

John: "Hi Teacher, What is your favourite movie ?".
Chemistry Teacher: "Indium Cerium Platinum Iodine Oxygen Nitrogen".
Ten seconds later... John replied I got it.

Do you?

There is a straight highway. Four different villages lie on that highway. The distance between them is different. The third village is 60km away from the first village; the fourth is 40 km away from the second; the third is 10 km near to the fourth that it is to the second.

Can you calculate the distance between the fourth and the first village ?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

What number do you get when you multiply all of the numbers on a telephone's number pad?

Why do Chinese men eat more rice than Japanese men do ?