Difficulty: Easy
Correct Answer: 27
Explanation:
Introduction / Context:
Finding cube roots of perfect cubes can be done by recognizing patterns or recalling standard cubes. Here, 19,683 is a well-known perfect cube in aptitude exams.
Given Data / Assumptions:
Number = 19,683; we seek n such that n^3 = 19,683.
Concept / Approach:
Check nearby cubes: 20^3 = 8000, 25^3 = 15,625, 27^3 = 19,683, 30^3 = 27,000. The exact match is 27^3.
Step-by-Step Solution:
Verification / Alternative check:
Prime factors: 19,683 = 3^9. Then cube root = 3^(9/3) = 3^3 = 27.
Why Other Options Are Wrong:
25, 26, 28 and 24 cubes do not equal 19,683.
Common Pitfalls:
Confusing with 28^3 = 21,952 or 26^3 = 17,576; quick memory of key cubes helps.
Final Answer:
27
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