Compute the cube root: What is the cube root of 19,683?

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:

27 * 27 = 729729 * 27 = 19,683


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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