Standard Form

MathematicsAQAEdexcelGCSEUnit: Number
Free taster
5 of 6 sections open
The basics

Numbers Beyond Imagination

Numbers Beyond Imagination

The distance to the nearest star is 40,000,000,000,000 km. The width of a virus is 0.000000020 metres. Writing these numbers is unwieldy and error-prone. Standard form (scientific notation) gives us a powerful way to express very large and very small numbers clearly. From astronomers measuring galaxies to biologists studying cells, standard form is the universal language of scale.
What is Standard Form?: A number written as a × 10ⁿ Where: • 1 ≤ a < 10 (at least 1, less than 10) • n is an integer (whole number) Example: 3.5 × 10⁴
Key terms

Mathematics glossary

What is Standard Form?
A number written as a × 10ⁿ Where: • 1 ≤ a < 10 (at least 1, less than 10) • n is an integer (whole number) Example: 3.5 × 10⁴
Exam tip

Earn the mark scheme marks

Common Mistakes to Avoid

❌ Wrong: 45 × 10³ ✅ Right: 4.5 × 10⁴

The first number must be between 1 and 10

❌ Wrong: 0.5 × 10⁴ ✅ Right: 5 × 10³

0.5 is less than 1 - not valid standard form

❌ Wrong: 3.2 × 10⁻³ = 3200 ✅ Right: 3.2 × 10⁻³ = 0.0032

Negative power means small number

❌ Wrong: Counting decimal places ✅ Right: Count how far decimal moves

Focus on decimal point movement, not places

Now try it yourself

Quiz · Question 1 of 14

Which of these numbers is written in standard form?

Tap an answer to check it

Revise every Mathematics topic, free during alpha

Standard Form is one of 127 topics on PrepWise — all aligned to your exam board.

Start revising free →