Variance Variance (?2) 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 Read More …

# Category: Mathematics and Stastics

## Contribution Of Aryabhatta In Mathematics

? Contribution of aryabhatta in mathematics Number notation Numerical values He made a notation system in which digits are denoted with the help of alphabet numerals e.g., 1 = ka, 2 = Kha, etc. Aryabhatta assigned numerical values to Read More …

## Fractions Or Rational Number

? Fractions Any unit can be divided into any numbers of equal parts, one or more of this parts is called fraction of that unit. e.g. one-forth (1/4), one-third (1/3), three-seventh (3/7) etc. The lower part indicates the number of equal parts Read More …

## Tips And Tricks For Speedy Calculations Module 2 Roots

? TIPS AND TRICKS FOR SPEEDY CALCULATIONS – MODULE III – MULTIPLICATION In this module we deal with techniques using which we can multiply two numbers in an unorthodox but quick manner. Firstly we take up some specific Read More …

## Age Problems

? 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 Read More …

## Multiplying Fractions And Ratio And Proportion

? Multiplying Fractions There are 3 simple steps to multiply fractions Multiply the top numbers (the numerators). Multiply the bottom numbers (the denominators). Simplify the fraction if needed. example: 1 / 2 × 2 / 5 Read More …

## Average Or Ap

? Average What is Average? The result obtained by adding several quantities together and then dividing this total by the number of quantities is called Average. The main term of average is equal distribution of a value among all which Read More …

## Simple Interest

? MATHEMATICS AND QUATITUATIVE APTITUDE – SIMPLE INTEREST Introduction Money is not free and it costs to borrow the money. Normally, the borrower has to pay an extra amount in addition to the amount he had borrowed. i.e, to Read More …

## Square Roots And Cube Roots

? Square Root & Cube Root Step 1: First of all group the number in pairs of 2 starting from the right. Step 2: To get the ten’s place digit, Find the nearest square (equivalent or greater than or less Read More …

## Percentage

? Important Formulas – Percentage Percentage Percent means for every 100 So, when percent is calculated for any value, it means that we calculate the value for every 100 of the reference value. percent is denoted 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 Read More …

## Direction Test

? 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 Read More …

## Number System

? Number system 1. Basic Formulae (a + b)(a – b) = (a2 – b2) (a + b)2 = (a2 + b2 + 2ab) (a – b)2 = (a2 + b2 – 2ab) (a + b + c)2 = a2 + b2 + c2 + 2(ab + bc + ca) (a3 + b3) = (a + b)(a2 – ab + b2) (a3 – b3) = (a – b)(a2 + ab + b2) (a3 + b3 + c3 – 3abc) = (a + b + c)(a2 + b2 + c2 – ab – bc – ac) When a + b + c = 0, then a3 + b3 + c3 = 3abc 2. 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 Read More …

## Data Interpretation

? Data interpretation Data Interpretation or DI refers to the implementation of procedures through which data is reviewed for the purpose of arriving at an inference. Data can be obtained from multiple sources e.g. data from running of industries, Read More …

## Vedic Maths

? Vedic maths: Square Example : Find square of 12 Step 1 1010 is the nearest power of 1010 which can be taken as our base. The deviation to our base =12?10=2=12?10=2 (To find the deviation, just remove the leftmost digit “11” and you Read More …

## Banking

? Commercial mathematics Banking Banking can be defined literarily as the business activity of accepting and safeguarding money owned by individuals and entities and release of the money whenever the needs arise by the owner. It is the business Read More …

## ClassificationL 1

? 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 Read More …

## Number System, Fractions

? Data analysis Data analysis is a primary component of data mining and Business Intelligence (BI) and is key to gaining the insight that drives business decisions. Organizations and enterprises analyze data from a multitude of sources using Big Read More …

## Area Of Triangle

? Area of triangle The area of triangles can be found by using the following formula: Area = Base × height / 2 The red line represents the length of the base (call it b if you want) Read More …

## Chain Rule

? CHAIN RULE This module will teach you the basics of direct and indirect proportions. These concepts will further help you in time and work questions. Important Formulas – chain rule Direct Proportion Read More …

## Tips And Tricks For Speedy Calculations Module 4 Division

? TIPS AND TRICKS FOR SPEEDY CALCULATIONS – MODULE IV – DIVISION Division is no more tedious as it used to be! In this module we deal with divisibility rules of various numbers, how to find remainders and 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 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 Read More …

## Fractions

? Fractions Any unit can be divided into any numbers of equal parts, one or more of this parts is called fraction of that unit. e.g. one-forth (1/4), one-third (1/3), three-seventh (3/7) etc. The lower part indicates the number of equal parts Read More …

## Averages

? Average The word “average” is used in everyday life to describe where the middle number of a data set is. It’s the typical number you would expect to find in a series of numbers. In statistics, the average Read More …

## Time & Work

? TIME AND WORK In these problems the number of persons, quantity of work done and time taken are important factors. Also time taken by a person depends on the efficiency of that person which comes 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 Read More …

## Concepts Of Geometry

? Concepts of geometry Points, Lines & Planes The most fundamental geometric form is a point. It is represented as a dot with a capital alphabet which is its name. A line is a set of points and Read More …

## Calculation Of Income Tax

? Calculation of income tax (for salaried person and excluding house rent allowance) Salary is made up of various components such as: Basic salary, House rent allowance (HRA), Special allowance Other allowances, reimbursements etc. However, Read More …

## Pie

? Pie-chart A pie graph (or pie chart) is a specialized graph used in statistics. The independent variable is plotted around a circle in either a clockwise direction or a counterclockwise direction.The dependent variable (usually a percentage) is rendered Read More …

## Simplification

? Simplification Simplification is one of the most important part of Quantitative Aptitude section of any competitive exam. Today I am sharing all the techniques to solve Simplification questions quickly. Rules of Simplification V ? Vinculum B ? Remove Brackets – Read More …

## Computer Binary Digit System

? 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 Read More …

## Surds And Indices

? Surds A surd is a square root which cannot be reduced to a rational number. For example, is not a surd. However is a surd. If you use a calculator, you will see that and we will need to Read More …

## Algorithm Method

? Algorithm method – meaning and quality, indefinate, definite In mathematics, computing, linguistics and related subjects, an algorithm is a sequence of finite instructions, often used for calculation and data processing. It is formally a type of effective method 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 Read More …

## Hcf And Lcm

? HCF & LCM HCF & LCM are acronym for words, Highest common factor and Lowest common multiple respectively. 1. H. C. F While we all know what a multiplication is like 2 * 3 = 6. HCF 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 Read More …

## Change Of Binary Number To Decimal Number And Decimal Number To Binary Number

? 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 Read More …

## Time And Distance And Intrest

? Time and distance Relationship between speed, distance and time Speed = Distance / Time or Distance = Speed × Time Average Speed = 2xy / x+y where x km/hr is a speed for certain distance and y km/hr Read More …

## Tips And Tricks For Speedy Calculations Module 3 Multiplication

? TIPS AND TRICKS FOR SPEEDY CALCULATIONS – MODULE III – MULTIPLICATION In this module we deal with techniques using which we can multiply two numbers in an unorthodox but quick manner. Firstly we take up some specific Read More …

## Discounts

? Discount The discount is referred to the reduction in the price of some commodity or service. It may anywhere appear in the distribution channel in the form of modifications in marked price (printed on the item) or in retail price (set by retailer Read More …

## Addition And Subtraction In Vedic Maths

? Addition and subtraction in vedic maths Vedic maths Addition Usually if we want to add to numbers say 52 and 66 we would add the unit digits. and if there is any remainder we will bring it to Read More …

## AnalogyLevel1

? Analogy Level-1 ANALOGY LEVEL 1 When you draw an analogy between two things we compare them for the purpose of explanation. If a scientist says that earth’s forest functions as human lungs then we instantly draw an 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 Read More …

## Prepositions

? Prepositions Prepositions are short words (on, in, to) that usually stand in front of nouns (sometimes also in front of gerund verbs). Even advanced learners of English find prepositions difficult, as a 1:1 translation is usually not possible. Read More …

## Calculation Of Interest On

? calculation of interest on/in savings account, fixed deposit account and recurring deposit account Saving account Interest rate calculation Formula Daily interest = Amount (Daily balance) * Interest (3.5/100) / days in the year. Earlier method of interest rate Read More …

## Height And Distance

? 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 Read More …

## Partnership

? 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 Read More …

## Relative Speed And Train Questions

? 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 Read More …