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GATE 2023 CY – Question 10

General Aptitude · Spatial Aptitude: Spatial Reasoning and Visualization · 2 marks · Multiple choice

A 100 cm × 32 cm sheet is folded five times, each time aligning one long edge with the opposite long edge, giving a 100 cm × 1 cm rectangle. The total number of creases visible when unfolded is ______.

  1. 32
  2. 5
  3. 31
  4. 63

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Show answer and explanation

Correct answer: (C) 31

Explanation

Five folds divide the width into 2⁵=32 strips when unfolded. Adjacent strips are separated by one crease, so there are32−1=**31, C**. Equivalently, the crease count obeysNnew=2Nold+1 starting at zero.