11, 10, ?, 100, 1001, 1000, 10001

1.	11, 10, ?, 100, 1001, 1000, 10001
Answer» The pattern is - 1, x 10 + 1, - 1, x 10 + 1, - 1, x 10 + 1, ..... So, missing term = 10 x 10 + 1 = 101.

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