What is scientific notation?

• A. A number written as a coefficient between 1 and 10 multiplied by a power of 10
• B. A method for writing numbers as sums of digits
• C. A way to express numbers as fractions
• D. A form of notation for angles

Answer: (A)

Scientific notation expresses a number as a product of a coefficient between 1 and 10 and a power of 10. This keeps very large or very small values compact and makes calculations easier, since you can focus on the coefficients and powers of 10 separately. For example, 320,000 becomes 3.2 × 10^5, and 0.0046 becomes 4.6 × 10^-3. The rule is that the coefficient must be at least 1 but less than 10, and the exponent shows how many times you move the decimal point. This approach is different from writing a number as a sum of digits (expanded form), expressing numbers as fractions, or using angle notation.