Category: Quantitative Aptitude

Probability




  Probability is the measure of how likely an event is. And an event is one or more outcomes of an experiment. Probability formula is the ratio of number of favorable outcomes to the...

Number System




Types of Numbers: I. Natural Numbers: Counting numbers are called natural numbers e.g. 1,2,3,5,6..and so on. II. Whole Numbers: All counting numbers together with zero form the set of whole numbers. e.g. 0,1,2,3,4,5 and...

Permutation & Combination




Combination A. Useful Relations (i).   0!=1!=1 (ii).  Con=n!0!*n!=10!=1 (iii). n!=n*(n−1)! (iv). Prn=n!(n−r)! (v). (n+1).Prn=Pr+1n+1 (vi). Crn=Prnr! (vii).Crn=Cn−rn (viii).Cr−1n−1+Crn−1=Crn   2. Fundamental Principle of Counting Let us now solve the problem mentioned in the introduction. We will write...