Terms used in Statistics

A student represents his scores in Mathematics . Statistics and Economics in a pie- chart. The central angle for Mathematics is 120^(@) . He scored 96 in Statistics and 84 in Economics. The central angle for Statistics is :

60 students of Section A of Class XI, obtained 40 mean marks in Statistics, 40 students of Section B obtained 35 mean marks in Statistics. Find out mean marks in Statistics for Class XI as a whole.

Among the examinees in an examination, 25%,30% and 45% failed in statistics, in mathematics and in at least one of statistics and mathematics respectively. An examinee is selected at random. Find the probabilities that (i) he failed in statistics only (ii) he passed in statistics if it is known that he failed in mathematics.

Nature Of Statistics

Why statistics ?