Identify the odd term: 16, 25, 36, 72, 144, 196, 225.
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A36
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B72
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C196
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D225
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ENone of these
Answer
Correct Answer: 72
Explanation
Introduction / Context:This list contains mostly perfect squares; the aim is to pick the solitary non-square. Recognizing squares up to at least 15^2 is enough to answer confidently.
Given Data / Assumptions:
- 16 = 4^2, 25 = 5^2, 36 = 6^2
- 144 = 12^2, 196 = 14^2, 225 = 15^2
- 72 is not a perfect square
Concept / Approach:Check each number for being an exact square. One term will not match any n^2 with integer n; that is the odd one out.
Step-by-Step Solution:Confirm squares: 16, 25, 36, 144, 196, 22572 falls between 8^2 = 64 and 9^2 = 81 → not a squareHence 72 is the odd term
Verification / Alternative check:Prime factorization: 72 = 2^3 * 3^2 — an odd exponent remains, so it cannot be a perfect square.
Why Other Options Are Wrong:36/196/225 are perfect squares and conform to the theme.
Common Pitfalls:Confusing 144 as non-square; it is 12^2. Rapid recognition of common squares prevents such slips.
Final Answer:72