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Railways PYQCBT 2 2017

RRB NTPC · Question 54

Fill in the blank. 11, 10, _______, 100, 1001, 1000, 10001....

  1. 110

  2. 101

  3. 100

  4. 111

Show answer & explanation

Answer: (B) 101

Explanation

The series alternates: 11, 10, 101, 100, 1001, 1000, 10001 – each pair is 1…1 followed by 1…0, with one more zero each time. The blank is 101.