Aurelie buys number of books for Rs60. If she had bought 2 more books for the same amount, each book would have cost Rs1 less. How many books did she buy?

A bag contains 5 red balls, 3 blue balls, and 8 green balls. Patrice draws 2 balls out of the bag. What is the probability that he gets a green ball and a blue ball?

Following chart shows number of students in a school who got distinction in one of three subjects. Find the number of students who got distinction in History and Maths.