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Great Mathematicians NCERT wants class 9 students to know......

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               (consider clicking the follow button for our efforts. It is similar to subscribe in YouTube) Pythagoras (569 BCE – 479 BCE) The Pythagoreans in Greece, followers of the famous mathematician and philosopher Pythagoras, were the first to discover the numbers which were not rationals, around 400 BC. These numbers are called irrational numbers (irrationals), because they cannot be written in the form of a ratio of integers. There are many myths surrounding the discovery of irrational numbers by the Pythagorean, Hippacus of Croton. In all the myths, Hippacus has an unfortunate end, either for discovering that √2 is irrational or for disclosing the secret about √2 to people outside the secret Pythagorean sect ! G. Cantor (1845-1918)  &  R. Dedekind (1831-1916)   In the 1870s two German mathematicians, Cantor and Dedekind, showed that: Corresponding to every real number, there is a point on the real n...

NCERT Class-9 Maths Chapter-15: Probability

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               (consider clicking the follow button for our efforts. It is similar to subscribe in YouTube) NCERT Class-9 Maths Chapter-15:Probability  Questions with step-by-step answers Exercise-15.1 1. In a cricket match, a batswoman hits a boundary 6 times out of 30 balls she plays. Find the probability that she did not hit a boundary.   2. 1500 families with 2 children were selected randomly, and the following data were recorded: Compute the probability of a family, chosen at random, having                                       (i) 2 girls (ii) 1 girl (iii) No girl                                              ...

NCERT Class-9 Maths Chapter-13: Surface Area and Volume

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               (consider clicking the follow button for our efforts. It is similar to subscribe in YouTube) NCERT Class-9 Maths Chapter-13:Surface Area and Volume  Questions with step-by-step answers Exercise-13.1 Answers:- Exercise-13.2 Answers:- Exercise-13.3 Answers:- Exercise-13.4 Answers:- Exercise-13.5 Answers:- Exercise-13.6 Answers:- Exercise-13.7 Answers:- Exercise-13.8 Answers:- Exercise-13.9 (Optional) Answers:-