Mathematics and Stastics

 Age Problems   Important Formulas on “Problems on Ages”:   1. If the current age is x, then n times the age is nx. 2. If the current age is x, then age n years later/hence = x + n. 3. If the current age is x, then age n years ago = x – n. 4. The ages in a ratio a : b will be ax and bx. 5. If the current age is x, … Read more

 Computer Binary digit system The binary number system, also called the base-2 number system, is a method of representing numbers that counts by using combinations of only two numerals: zero (0) and one (1). Computers use the binary number system to manipulate and store all of their data including numbers, words, videos, graphics, … Read more

 Direction test     Introduction: There are four main directions – East, West, North and South as shown below:         There are four cardinal directions – North-East (N-E), North-West (N-W), South-East (S-E), and South-West (S-W) as shown below:       Key points   At the time of sunrise if a man stands facing the east, his shadow will be towards … Read more

 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

 Change of binary number to decimal number and decimal number to binary number Binary Number System Digital computer represents all kinds of data and information in the binary system. Binary Number System consists of two digits 0 and 1. Its base is 2. Each digit or bit in binary number system can be … Read more

 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

 Analogy Level-1   CLASSIFICATION LEVEL 1 Classification involves putting things into a class or group according to particular characteristics so it’s easier to make sense of them, whether you’re organizing your shoes, your stock portfolio, or a group of invertebrates.  From all competitive examination classification is one of the most important topics, this … Read more

 Height and Distance This topic has many practical application in day to day life. In engineering stage it is used in surveying. The basic purpose is to find the unknown variables by observing the angle of the line of sight. This is done by using some the fact that in … Read more

 PARTNERSHIP   Partnership : Partnership is an association of two or more parties, they put money for business.         Simple Partnership: Simple partnership is one in which the capitals of the partners are invested for the same time. The profit or losses are divided among the partners in the ratio … Read more

 RELATIVE SPEEED AND TRAIN QUESTIONS Speed has no sense of direction unlike the velocity. Relative speed is the speed of one object as observed from another moving object. Questions on train are the classic examples of relative speed and in all these questions it is assumed that trains move parallel … Read more