Odd number triad: the one not in geometric progression (powers of one base)

This type of question, asked 2 times: 13 Sep 2025 S2, 18 Sep 2025 S1. All 2 questions below, oldest first.

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Question 1
13 Sep 2025 S2
17 $Choose the odd one:$
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Question 2
18 Sep 2025 S1
18 $Which of the following groups does not follow the same arithmetic rule?$
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