A circle is a locus of all points which are equidistant from a point. If O is a fixed point in a given plane, the set of points in the plane which are at equal distances from O will form a circle.

A triangle is a polygon of three sides. Sum of the angles of a triangle is 180 degrees. Triangles are classified in two general ways: by their sides and by their angles.

Geometry is branch of mathematics concerned with shapes, sizes and properties of figures. Geometry includes knowledge of angles, lines, triangles, quadrilaterals, circles and polygons.

Ratio is a relation between two quantities or numbers. It is a relation that one quantity bears to another with respect to magnitude. A ratio of a and is denoted by a : b and is read as a is to b. In a ratio, the first part (a) is called antecedent and second part (b) is called consequent.

The terms percent means for every hundred. Percentage is a way of expressing a number as a fraction of 100. It is denoted by using the percent sign, %. For example, when a person made a profit of 20 percent, it means that the person gained Rs. 20 for every hundred rupees invested in the business. Scoring 60 percent marks means out of every 100 marks the candidate scored 60 marks.

Average is defined as the ratio of sum of the quantities to the number of quantities. Average or mean is said to be a measure of central tendency.

A divisibility rule is a method to determine whether a given integer is divisible by a fixed divisor without performing the division. You can do this by examining the digits of the integer.

Number Systems forms the base for Quantitative Ability and clearing of concepts is important for CAT and other management exams. A measurement carried out, of any quantity, leads to a meaningful value called the Number. This value may be positive or negative depending on the direction of the measurement and can be represented on the number line.

Suppose there are two numbers, a and b. If a number a divides another number b exactly, then a is factor of b and b is called multiple of a.

In daily life, there are situations where we need to complete a particular job in a reasonable time. We have to complete the project earlier or later depending upon the needs. Accordingly, the men on duty have to be increased or decreased. The time and the men engaged for a project are inversely proportional to each other. The more the number of men involved, the lesser is the time required to finish a job.

The terms "Time" and "Distance" are related to the speed of a moving object. The questions on speed, time and distance are based on one general formula: Distance = Speed × Time