How can you take 2 from 5 and leave 4?

Arrange the numbers 1, 2, 3, 4, 5, 6, 7, 8 and 9 above and below the division line in a manner that the thus formed fractions equal to 1/3.

(You can use one number only once)

You have a basket containing ten apples. You have ten friends, who each desire an apple. You give each of your friends one apple.
Now all your friends have one apple each, yet there is an apple remaining in the basket.
How?

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?

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?

Replace all '*' with digits 1, 2, 3, 4, 5 and 6 to make below statement true.

* *
x *
=====
* * *

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

Eight of us go fourth, not back, to protect our king from an attack. What are we?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?