Standard Form

This lesson covers standard form (also called standard index form or scientific notation) for AQA GCSE Mathematics. Standard form is used to write very large or very small numbers in a compact and manageable way. You need to be able to convert numbers into and out of standard form, and perform calculations with numbers in standard form.

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What Is Standard Form?

A number in standard form is written as:

a x 10 to the power n

where:

• a is a number between 1 and 10 (1 <= a < 10)
• n is an integer (positive or negative)

Examples

Ordinary Number	Standard Form
4,500	4.5 x 10 cubed
72,000,000	7.2 x 10 to the power 7
340	3.4 x 10 squared
0.006	6 x 10 to the power (-3)
0.0000045	4.5 x 10 to the power (-6)
9,100,000	9.1 x 10 to the power 6