Year 9: Scientific notation

Scientific notation is a way of writing very large or very small numbers in a shorter, more convenient form.

What is Scientific Notation?

It’s based on powers of 10. It looks like this: a x 10^b, where a is a number between 1 and 10 (but can be 1), and b is an integer (whole number) that shows how many places to move the decimal point.

How to Convert Numbers

From Decimal to Scientific Notation

1. Large Numbers: Count the number of digits after the decimal point. This is the power of 10.
2. Example: 67000000 = 6.7 x 10⁷
3. Example: 0.0000045 = 4.5 x 10^-6

From Scientific Notation to Decimal

To convert from scientific notation, multiply by 10 raised to the power shown in the exponent.

Example: 3.2 x 10⁴ = 32000

Key Points

• Use ‘x’ to represent multiplication.
• The exponent tells you how many places to move the decimal point.
• Be careful with negative exponents (e.g., 2.5 x 10^-3).