Multiple choice

In the following number series, a wrong number is given. Find out the wrong number. 5 , 4 , 6 , 15, 55 , 275

  1. 55

  2. 15

  3. 6

  4. 275

  5. 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pattern: each term equals (previous term × n) - n where n = 1, 2, 3, 4, 5. Verifying: 5×1-1=4, 4×2-2=6, 6×3-3=15, 15×4-4=56 (not 55), 56×5-5=275. So 55 is wrong; it should be 56.

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