# Converting large numbers into standard form

In this lesson you will learn how to convert large numbers into standard form.

This lesson includes:

• a video
• an activity worksheet

Created in partnership with GCSEPod.

# Learn

### Standard form

Standard form is a useful way of writing very large or very small numbers. Standard form is used a lot in science when working with very large numbers, such as in astrophysics for example.

There are two parts to a number when it is represented in standard form, usually:

A × 10ⁿ

• A is a number, which must be between 1 and 10.
• is called the index.
• is the power of 10 we multiply A by, to return to the original number.

For example, 42000 can be written as 4.2 × 10⁴
because 4.2 × 10000 = 42000.

Watch this short video from GCSEPod which explains how to write large numbers in standard form. You might find it helpful to watch it twice and make notes on the second watch through.

# Practise

## Activity 1

Standard form challenge

Download the standard form multiple choice quiz below. You can print it out, or use a pen and paper to answer the questions. The answers are included at the end of the sheet.

## Activity 2

Standard form match up

Test your knowledge and see if you can you match up the integer values with the equivalent standard form values.