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GATE 2026 MA – Question 5

General Aptitude · Spatial Aptitude: Spatial Reasoning and Visualization · 1 mark · Multiple choice

H denotes a head-up coin and T a tail-up coin. Six coins begin HHHTTT and must become TTTHHH, as shown. A step swaps two adjacent coins without flipping either. Find the minimum steps.

Diagram for GATE 2026 MA question 5
  1. 3
  2. 6
  3. 9
  4. 12

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Show answer and explanation

Correct answer: (C) 9

Explanation

Each of the three H coins must cross each of the three T coins. These nine H–T crossings each require an adjacent swap, giving a lower bound of nine. Moving each T left across all three H coins attains it. **9, C**.

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