There was an aeroplane crash, every single person died, but two people survived. How is this possible?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

I am dry when I go inside, but wet when I am pulled outside.
The longer I am inside, the stronger I get
When I am completely out, I am wet and I literally sag
Who am I?

Using four sevens (7) and a one (1) create the number 100. Except for the five numerals, you can use the usual mathematical operations (+, -, x, :), root and brackets ()

Solve the mathematical equation in the picture below.

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

A fresh card pile is taken out of a box (the pile has 54 cards including 2 jokers). One joker is taken out and then the cards are shuffled for a good amount of times. After shuffling, two piles are made by dividing that one pile.



What is the possibility that one of the piles will have a card sequence from A to K in order?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

Which is faster, Heat or Cold ? Explain.

Considering the below equation:

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?