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Find the wrong term in the series: 7, 15, 31, 63, 128, 255.

Competition practiceNumber Series
  • A63
  • B31
  • C255
  • D128

Step-by-Step Solution

Pattern is ×2 + 1: 7, 15, 31, 63, 127, 255. So 128 should be 127; 128 is the wrong term.
Answer: D) 128

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