Standard Form

Summary and Exam Tips for Standard Form

Standard Form is a subtopic of Numbers and the Number System, which falls under the subject Mathematics in the Edexcel IGCSE curriculum. Standard form is a concise way to express large numbers using powers of ten. In this notation, $A$ must be a number such that $1 \leq A < 10$, and it is always multiplied by $10^n$, where $n$ is an integer. For example, $3.2 \times 10^5$ is in standard form. To convert a number from standard form to an ordinary number, multiply $A$ by $10^n$. For instance, $4.2 \times 10^5$ equals 420,000. Conversely, to write a large number like 56,700,000 in standard form, move the decimal point left until the number is between 1 and 10, resulting in $5.67 \times 10^7$. This process involves counting the decimal shifts to determine the power of ten. Calculators can assist in these conversions by following specific input steps to achieve the desired result.

Exam Tips

• Understand the Basics: Ensure you know that in standard form, $1 \leq A < 10$ and the number is expressed as $A \times 10^n$.
• Conversion Practice: Regularly practice converting between standard form and ordinary numbers to build confidence and speed.
• Calculator Skills: Familiarize yourself with using a calculator for standard form conversions, as it can save time during exams.
• Decimal Point Movement: When converting large numbers to standard form, carefully count the decimal point shifts to determine the correct power of ten.
• Check Your Work: Always double-check your calculations to avoid simple errors, especially with powers of ten.