Multiple choice

A series is given, with one term missing,choose the correct alternative from the given ones that will complete the series. 13, 10, ?, 100, 1003, 1000, 10003

  1. 130

  2. 1030

  3. 1130

  4. 103
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The pattern alternates between operations: 13 → 10 (subtract 3), 10 → ? (add something), ? → 100, 100 → 1003 (add 903? No). Let's see the claimed answer 103: 13, 10, 103, 100, 1003, 1000, 10003. Pattern: subtract 3, then add 93, subtract 3, add 903, subtract 3, add 9003. The additions are 93, 903, 9003 — each is 9×10^(n)+3? Actually 93 = 90+3, 903 = 900+3, 9003 = 9000+3, and 10003 = 10000+3. Yes! Pattern: (×10−?+3)?

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