Difficulty: Easy
Correct Answer: 8
Explanation:
Introduction / Context:When multiplying or dividing powers with the same base, exponents add or subtract respectively. This is a direct application of the indices laws that allows consolidation to a single power of the base 16.
Given Data / Assumptions:
Concept / Approach:Use two rules: a^m ÷ a^n = a^(m − n) and a^m × a^n = a^(m + n). Apply them in sequence to combine all powers into a single exponent k.
Step-by-Step Solution:
First division: 16^9 ÷ 16^4 = 16^(9 − 4) = 16^5.Then multiply by 16^3: 16^5 × 16^3 = 16^(5 + 3) = 16^8.So k = 8.Verification / Alternative check:Rearranging the order (multiplication before division) still yields 9 − 4 + 3 = 8, confirming consistency.
Why Other Options Are Wrong:
Common Pitfalls:Applying multiplication and division in the wrong way to the exponents. Keep track: divide ⇒ subtract; multiply ⇒ add.
Final Answer:8
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