Which statement about scientific notation is true?

Which statement about scientific notation is true?

• A. It is used to express very large or very small numbers.
• B. It expresses only integers.
• C. It is a unit of measurement.
• D. It is a form of decimal notation.

Answer: (A)

Scientific notation expresses numbers that are extremely large or extremely small by writing them as a coefficient between 1 and 10 multiplied by a power of ten. This format is used precisely to capture the scale of such numbers and to simplify calculations and comparisons across orders of magnitude. Because of that, the statement that it is used to express very large or very small numbers is the correct description. It's not a unit of measurement, and it's not limited to integers—the coefficient can be a decimal, and the exponent can be any integer to shift the decimal point. Nor is it simply decimal notation; the power-of-ten factor distinguishes scientific notation from standard decimal notation. For example, 3.0 × 10^8 meters per second or 1.67 × 10^-27 kilograms illustrate how it compactly conveys huge or tiny values.

Scientific notation expresses numbers that are extremely large or extremely small by writing them as a coefficient between 1 and 10 multiplied by a power of ten. This format is used precisely to capture the scale of such numbers and to simplify calculations and comparisons across orders of magnitude. Because of that, the statement that it is used to express very large or very small numbers is the correct description. It's not a unit of measurement, and it's not limited to integers—the coefficient can be a decimal, and the exponent can be any integer to shift the decimal point. Nor is it simply decimal notation; the power-of-ten factor distinguishes scientific notation from standard decimal notation. For example, 3.0 × 10^8 meters per second or 1.67 × 10^-27 kilograms illustrate how it compactly conveys huge or tiny values.