Mathematics and Stastics

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

 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

 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 the tens digit and atlast we will add the tens digit. Now we will do … Read more

 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 calculation   Earlier, banks would pay interest at the rate of 3.5% p.a. on the … Read more

 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 – in the order ( ) , { }, [ ]  O → Of D → Division M … Read more

 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

   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 general division rules. After reading this module and solving problems by heart you may find … Read more

 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 explanation that both lungs and trees intake important elements from air. As far as SSC … Read more

   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 cases using which we come to generalized multiplication of any two given numbers. Multiplying two … Read more

 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 the 33 consonants of the Indian alphabet to represent 1,2,3…25,30,40,50,60,70,80,90,100. Notation system  He invented a … Read more