All linear dimensions of a coil's core are multiplied by a factor: factor change in self-inductance

The same question, asked 2 times: 16 May 2023 S2*, 21 Apr 2025 S2. Every wording below, oldest first.

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Question 1
16 May 2023 S2
47 $A coil is wound on a core of rectangular cross-section. If all the linear dimensions of the core are increased by a factor 2 and number of turns per unit length of coil remains same, the self-inductance increases by a factor of (Assume permeability is same)$
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Question 2
21 Apr 2025 S2
12 $A coil is wound on a core of rectangular cross-section. If all the linear dimensions of core are increased by a factor 3 and number of turns per unit length of coil remains same, the self-inductance increases by a factor$
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Question 1