Scientific Notation
Scientific notation transforms unwieldy numbers like 93,000,000 miles (Earth to Sun) into the elegant 9.3 × 10⁷. Year 8 students often struggle with this GCSE foundation skill, particularly when moving decimal points and determining positive versus negative exponents.
Try it right now
Click “Generate a problem” to see a fresh example of this technique.
Why it matters
Scientific notation becomes essential across GCSE sciences and beyond. In physics, students encounter Planck's constant (6.63 × 10⁻³⁴ J·s) and the speed of light (3.0 × 10⁸ m/s). Chemistry requires expressing Avogadro's number (6.02 × 10²³) and atomic masses. Biology uses scientific notation for cell sizes (typical bacteria: 2 × 10⁻⁶ m) and population genetics. Computing students work with data storage—a terabyte equals 10¹² bytes. Without scientific notation, calculations involving very large or small quantities become unmanageable. Students who master this skill find A-level maths, physics, and chemistry significantly more accessible, as scientific calculators display results in this format by default for extreme values.
How to solve scientific notation
Scientific Notation
- Write as c × 10n where 1 ≤ c < 10.
- Count decimal places moved = exponent.
- Right = negative exponent, left = positive.
Example: 45000 = 4.5 × 10⁴.
Worked examples
Write 300 in scientific notation.
Answer: 3 × 102
- Move the decimal point → 300 = 3 × 10^2 — Move decimal 2 places left to get 3.
Write 660000 in scientific notation.
Answer: 6.6 × 105
- Find coefficient (1 ≤ c < 10) → 660000 = 6.6 × 10^5 — Coefficient is 6.6, exponent is 5.
(6 × 105) × (5 × 101) = _______
Answer: 3 × 107
- Multiply coefficients, add exponents → 6 × 5 = 30, 10^5 × 10^1 = 10^6 — Coefficients multiply normally, exponents add.
- Normalize → 3 × 10^7 — Adjust so coefficient is between 1 and 10.
Common mistakes
- Students write 4500 as 45 × 10² instead of 4.5 × 10³, forgetting the coefficient must be between 1 and 10.
- When converting 0.0032, students often write 32 × 10⁻⁴ rather than 3.2 × 10⁻³, miscounting decimal places moved.
- Multiplying (2 × 10³) × (3 × 10²), students calculate 6 × 10⁶ instead of 6 × 10⁵, incorrectly multiplying exponents rather than adding them.
- Converting large numbers like 850,000, students write 8.5 × 10⁴ instead of 8.5 × 10⁵, moving the decimal point the wrong number of places.