When 99 is considered higher than 100?

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

Solve the puzzle by telling what does below picture means.

In a secret society, a buried chamber can be accessed only via a secret password. The password is seven characters long and comprises of just letters and numbers.

You find a code that can help you in cracking the password. The code says "You force heaven to be empty".

Can you deduce the password from that?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

See the given image carefully. What you have to do is move the blue checkers in the position of the black checkers and vice versa. You are only allowed to move the checker to an adjacent empty space. Do it in the least possible moves.

My location can be determined by the below rebus.
So where am i ?

A man is surviving on an island along with his friend. They have been starving for four days for food. Suddenly, they find a fisherman. The friend goes with the fisherman in order to catch the fish (if they can find any).

The fisherman returns after some time but he is alone and has some salmon that he had prepared. When asked, the fisherman tells him that his best friend fell off the boat and drowned in the water. Starving for so long, he eats the meal while crying for his friend.

After being rescued, he goes to a diner and orders salmon. When he eats his meal, he jumps and commits suicide. Why did he do it?