It is the number system in which ten digits (i.e. 0, 1, 2, 3, 4, 5, 6, 7, 8 ,9 ) are used. Any whole number can be written using a combination of these ten digits. As it is based on the grouping of tens, it is also known as Decimal Number System or the Base Ten System. The value of each digit in a number depends on its place in the number.

Binary number system consists of two digits 0 and 1 and its base is 2. Each digit or bit in binary number system can be 0 or 1. It also provides the information about the Conversion of binary numbers to decimal number, Conversion of decimal number to binary number and Alternative method fo binary number system.

Quinary number system consists of five digits 0 to 4 and its base is 5. The number is expressed in the power of 5 in order to convert a quinary into decimal number.

This note gives the information about the H.C.F and L.C.M.

A perfect square number is the product of two integers among the whole number. It is the perfect root of a particular number.A number that creates a specified number when it is multiplied by itself is said to be a square root.