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GATE 2022 MT – Question 4

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

The figure shows a grid formed by a collection of unit squares. The unshaded unit square in the grid represents a hole. What is the maximum number of squares without a “hole in the interior” that can be formed within the 4 × 4 grid using the unit squares as building blocks?

Diagram for GATE 2022 MT question 4
  1. 15
  2. 20
  3. 21
  4. 26

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Show answer and explanation

Correct answer: (B) 20

Explanation

There are 15 available unit squares. Of nine possible 2×2 squares, four contain the hole, leaving five. Every 3×3 square and the 4×4 square contains it. Total **15+5=20, B**.