What will you call your mother's brother's brother-in-law?

Two trains start at the same time, one from Bangalore to Mysore and the other from Mysore to Bangalore. if they arrive at their destinations one hour and four hours respectively after passing one another, how much faster is one train running than the other?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

How many letters are in the alphabet?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

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?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

Name a key which is hardest to turn.

How could a baby fall out of a twenty-story building onto the ground and live?