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mixtures and alligations problems

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Alligation rule is used to determine the exact proportion to mix two ingredients of any price to obtain a mixture with estimated cost. Mean price: Cost price of the mixture per unit. suppose a container contains x units of liquid out of which y units are replaced then quantity of liquid after n such operations left in container would be x(1-y/x)^n  Alligation rule: Quantity of cheap ingredient(b) : Quantity of costly ingredient (a)= x2-x1 : x1-x0 point to remember: cost price of mixture always lies between two costs. Consider the graph Quantity v/s Cost , with this method one can solve problems with more ease A: Type of cheaper ingredient. B: Type of costly ingredient. x0: cost of cheaper ingredient. x1: cost of mixture. x2: cost of costly ingredient. Quantity of cheap ingredient : Quantity of costly ingredient = x2-x1 : x1-x0

Deductions

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This is a part of Logical ability section, we are supposed to draw conclusions using given existing data but not from our usual life it's something life nature v/s nurture where we have to consider nurture but not generic nature, you will understand this by the end. Example All girls are women. Some women are pregnants. the conclusion can be: some girls are pregnants.(-or- some girls are not pregnants) Deduction: A form of reasoning with 2 premises and 3 terms.

Truth teller and lie detector problems

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The key idea of the truth teller identification in competitive exams is to test one's logical ability to answer questions and its usage is increasing day by day, It is the way to test your ability to identify the level truth or lie from many given inferences to draw some conclusion.From the given set of statements by few persons, has to draw a conclusion. Truth teller, Lie Detector.    Types of people in Truth teller and lie detector problems: Liar : A person who always lie. Truth Teller :A person who always says the truth. Alternator: A person whose answers always alters in a step fashion(example: if he say 3 statements, his statements' truthness can be either T, F, T or F, T, F)

Simple Interest aptitude tricks

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Well we are all aware of calculating simple interest in our regular life and perhaps many solve this on the go,even though this post is for some one who is trying to figure out how to calculate simple interest for a loan lend or borrowed. Terms: Simple Interest(SI):Cash to be paid for using other's money. Principal(P): Amount lend or Amount borrowed.

Remainders in math expressions

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A Remainder is the portion is left unused after doing some process,In this context remainder is a number which is left when a number is divided by another number. In the basic levels of our education,we learn how to find remainders of normal maths expressions like Remainder("5",4)=1 but what if the question is asked in the form of Remainder( "19*19*17*21*9" ,"5") calculation part requires more time than the time we get to solve the same in the exam if we follow traditional methods. Divisor A number by which another number to be divided.

Profit loss and discount problems

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One of the important roles of an organization is to ensure the overall performance based on profit as it is the only factor for organization's sustainability.so profit and loss problems have a great role in quantative aptitude. In general,profit can be defined as the financial gain and loss can be defined as the amount lost. There are few more terms which one should learn  Cost Price(C.P): Amount incurred for purchasing/manufacturing the product. Selling Price(S.P): Gained amount in process of selling the product.

Units place in math expression

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Many exams try to make you feel that you cannot solve the problem by making question as big as possible like units place of (186937)^178909 but solving this problem is as simple as solving 9%4 Before solving these kind of problems, understand the great concept called Cyclicity of numbers which states that any digit when multiplied by itself repeatedly, generates a cycle of digits. points to remember: Only units place will be responsible for generating units place Every number after applying successive multiplications,repeats the cycle of digits. So try to figure out a common series in powers of digits for example units(3)=3,units(3*3)=9,units(9*3)=7,units(7*3)=1,units(1*3)=3(we get a cycle of multiplication) Number      powers                         Series/cycle(units place of powers column) [cyclicity of number] 2                 2,4,8,16,32                   2,4,8,6                    [4] 3                 3,9,27,81,243               3,9,7,1