## Tips to solve Permutation and Combination Problems

Factorial Notation:Let n be a positive integer. Then, factorial n, denoted n! is defined as: n! = n(n – 1)(n – 2) … 3.2.1. Examples: We define 0! = 1.…

## Tips and Tricks on Boats and Streams related Aptitude Problems

Downstream/Upstream:In water, the direction along the stream is called downstream. And, the direction against the stream is called upstream. If the speed of a boat in still…

## Tips and Tricks to solve problems on Calendar

Odd Days: We are supposed to find the day of the week on a given date.For this, we use the concept of ‘odd days’. In a…

## Important notes on Sequence and Series

Important Concepts and Formulas – Sequence and Series Arithmetic Progression(AP)   Arithmetic progression(AP) or arithmetic sequence is a sequence of numbers in which each term after…

## Simple tricks to calculate average of numbers

AVERAGE An average or more accurately an arithmetic mean is, in crude terms, the sum of n different data divided by  n Averages of a…

## Tricks to Solve Problems on Percentage

Concept of Percentage:By a certain percent, we mean that many hundredths.Thus, x percent means x hundredths, written as x%. To express x% as a fraction: We have, x% = x . 100  …

## Tricks to solve Aptitude Problems – Profit and Loss

IMPORTANT FACTS Cost Price: The price, at which an article is purchased, is called its cost price, abbreviated as C.P. Selling Price: The price, at which an…

## Tips and Tricks to solve Simple Interest Problems

Principal:The money borrowed or lent out for a certain period is called the principal or the sum. Interest:Extra money paid for using other’s money is called interest. Simple Interest…

## Tips and Tricks on H.C.F and L.C.M

Factors and Multiples:If number a divided another number b exactly, we say that a is a factor of b.In this case, b is called a multiple of a. Highest Common Factor (H.C.F.) or Greatest Common Measure (G.C.M.) or Greatest…

## Short Tricks to Solve Problems on Area

FUNDAMENTAL CONCEPTS Results on Triangles: Sum of the angles of a triangle is 180°. The sum of any two sides of a triangle is greater…