Multiple choice general knowledge sports

A 30inches x 30inches square metal plate needs to be fixed by a carpenter on to a wooden board. The carpenter uses nails all along the edges of the square such that there are 31 nails on each side of the square. Each nail is at the same distance from the neighboring nails. How many nails does the carpenter use?

  1. 116

  2. 124

  3. 120

  4. 110
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is a classic counting problem where corner nails are shared between adjacent sides. If there are 31 nails on each side, the corners are counted twice. Total nails = (31 × 4) - 4 = 124 - 4 = 120. The 4 corner nails are subtracted because each was counted twice when multiplying 31 by 4.

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