Exponent rules with common base: Given 95^3.7 ÷ 95^0.9989 = 95^?, find the value of ? (choose the closest).
Correct Answer: 2.7
Introduction / Context:This is a direct application of the law of exponents for the same base: a^m / a^n = a^(m − n). The problem asks for the resulting exponent after division. Then select the closest value from the provided decimal options.
Given Data / Assumptions:
- Base = 95
- Exponents: 3.7 (numerator) and 0.9989 (denominator)
Concept / Approach:For equal-base division, subtract exponents. Therefore ? = 3.7 − 0.9989. Carry out the subtraction carefully to avoid decimal slips and compare with nearby choices (2.7, 2.99, etc.).
Step-by-Step Solution:
? = 3.7 − 0.9989= 2.7011Nearest listed option: 2.7Verification / Alternative check:Compute back: 95^2.7 × 95^0.9989 = 95^(3.6989) ≈ 95^3.7 with a tiny deficit of 0.0011, confirming that 2.7 is the nearest rounded exponent among choices.
Why Other Options Are Wrong:
- 2.99, 3: much larger than 2.7011.
- 1.9, 2.4: smaller than 2.7011.
Common Pitfalls:Reversing the subtraction order (0.9989 − 3.7), or mistakenly adding exponents when dividing like bases.
Final Answer:2.7