Use exponent rules to condense powers of 3: Evaluate 27^3 × 3^4 ÷ 3^10 and choose the correct value.

Difficulty: Easy

Correct Answer: 27

Explanation:


Introduction / Context:
This question tests consolidation of exponents using the same base. The key is to rewrite 27 as a power of 3 and then apply the rules for multiplying and dividing powers with the same base: add exponents when multiplying and subtract when dividing.


Given Data / Assumptions:

  • Expression: 27^3 × 3^4 ÷ 3^10.
  • Recall: 27 = 3^3.
  • Exponent rules: a^m * a^n = a^(m+n), and a^m / a^n = a^(m−n).


Concept / Approach:
Express all terms as powers of 3. Then use exponent laws to combine them into a single power of 3. Finally, evaluate that power or identify the corresponding integer.


Step-by-Step Solution:

Rewrite 27^3 as (3^3)^3 = 3^(9).Multiply: 3^9 × 3^4 = 3^(9+4) = 3^13.Divide by 3^10: 3^13 ÷ 3^10 = 3^(13−10) = 3^3.Evaluate: 3^3 = 27.


Verification / Alternative check:
You can also pair 3^4 ÷ 3^10 = 3^(−6) and then multiply 27^3 * 3^(−6) = 3^9 * 3^(−6) = 3^3 = 27.


Why Other Options Are Wrong:
9 and 81 are 3^2 and 3^4 respectively—off by exponent arithmetic; 1/27 corresponds to 3^(−3), which would arise from reversing the subtraction; 3 would require exponent 1.


Common Pitfalls:
Forgetting to convert 27 into 3^3, or subtracting exponents in the wrong order when dividing.


Final Answer:
27

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