Mathematics and Stastics

   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

 Vedic Mathematics Vedic Mathematics is a collection of Techniques/Sutras to solve mathematical arithmetics in easy and faster way. It consists of 16 Sutras (Formulae) and 13 sub-sutras (Sub Formulae) which can be used for problems involved in arithmetic, algebra, geometry, calculus, conics. Some vedic maths trics  Multiply a number by 9   Multiply … 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

 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) and the blue line represents the length of the height.   To get the area, … Read more

 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 than) to the first grouped pair from left and put the square root of the … Read more

 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. Types of Numbers I. Natural Numbers Counting numbers 1,2,3,4,5,…1,2,3,4,5,… are called natural numbers   … Read more

 BOAT AND STREAM Boat and stream problems is a sub-set of time, speed and distance type questions where in relative speed takes the foremost role. We always find several questions related to the above concept in SSC common graduate level exam as well as in bank PO exam. Upon listing … Read more

 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 into picture when different people do the work such as women, children do the work … Read more

 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 into which the unit is divided, is called denominator. The upper part, which indicates the number … Read more

     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 round the answer correct to a few decimal places. This makes it less accurate. If … Read more