Mantissa and Exponent

To store real numbers (numbers with decimal points), computers use a method called floating-point representation.

The decimal point is moved so that there is only one non-zero digit to the left of it. This new number is called the mantissa, and the number of places the decimal point was moved becomes the exponent.

With this in mind, computers would store the number 73185 as 0.73185 x 105.

Identifying the Mantissa

The mantissa is the number that follows the decimal place. 

0.73185 x 105

In this scenario, the mantissa is 73185.​

Identifying the Exponent

The exponent is the small number to the right of the full equation.

0.73185 x 105

In this scenario, the exponent is 5.

Being able to identify the mantissa and exponent will secure an easy mark or two in the National 5 exam.

National 5 Target

You should be able to identify the Mantissa and Exponent of a given floating point number.