Variance

Variance Variance (σ2) in statistics is a measurement of the spread between numbers in a data set. That is, it measures how far each number in the set is from the mean and therefore from every other number in the set. In investing, the variance of the returns among assets in a portfolio is analyzed … Read more

Puzzle Test

 Puzzle Test Puzzle Test section comprises problems put in the form of puzzles involving certain number of items, be it persons or things. The candidate is required to analyse the given information, condense it in a suitable form and answer the questions asked.     In this type of test, the questions are … Read more

Median

 Median Median is the middle number in a sorted list of numbers. To determine the median value in a sequence of numbers, the numbers must first be arranged in value order from lowest to highest. If there is an odd amount of numbers, the median value is the number that is in the … Read more

Time & Distance

 TIME & DISTANCE In this module we will deal with basic concepts of time and distance, speed, average speed, conversion from km/h to m/s and vice versa. This chapter will form the basis of further concept of relative speed which is used in train and boat problems. Important … Read more

Pipe And Cistern

 Pipes and Cistern   Inlet: A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet.   Outlet: A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet.   If a pipe can fill a tank in x hours, … Read more

Shrinivas Ramanujan

 Shrinivas Ramanujan: Contribution to mathematics Srinivasa Ramanujan, an Indian mathematician was born in 22nd December, 1887 in Madras, India. Like Sophie Germain, he received no formal education in mathematics but made important contributions to advancement of mathematics. His chief contribution in mathematics lies mainly in analysis, game theory and infinite series. He made … Read more

Relation Between Arc Radius And Angle

 Relation between arc radius and angle     Arc length   =   [radius • central angle (radians)] Arc length   =   circumference • [central angle (degrees) ÷ 360]     Proof of the trigonometric ratios of complementary allied angles Two acute angles are complementary to each other if their sum is equal to 90°. In … Read more

Contribution Of Brahma Gupta

 Contribution of  Brahma gupta, in mathematics Brahmagupta was born in 598 A.D.in Bhinmal city in the state of Rajasthan. He was a mathematician and astronomer, who wrote many important works on mathematics and astronomy. His best known work is the “Brahmasphuta‐siddhanta”, written in 628 AD in Bhinmal. He was the first to use … Read more

Mensuration (revised)

 MENSURATION Mensuration is the branch of mathematics which deals with the study of different geometrical shapes, their areas and Volume. In the broadest sense, it is all about the process of measurement. It is based on the use of algebraic equations and geometric calculations to provide measurement data regarding the width, depth and volume … Read more