Which of the following numbers is equivalent to 5.1 × 10^{-2}?

• A. 0.051
• B. 510
• C. 5
• D. 0.0051

Answer: (A)

Verified step by step guidance

1. Understand that the number 5.1 × 10^{-2} is written in scientific notation, where 5.1 is the coefficient and 10^{-2} indicates the decimal point moves 2 places to the left.
2. Rewrite the expression by moving the decimal point in 5.1 two places to the left because of the negative exponent: 5.1 → 0.051.
3. Compare the rewritten number 0.051 with the given options to find the equivalent decimal number.
4. Check each option: 510 is much larger, 5 is larger, 0.0051 is smaller, and 0.051 matches the converted number.
5. Conclude that 5.1 × 10^{-2} is equivalent to 0.051.