Multiple choice

Find the wrong term in the following number series. 7, 12, 40, 222, 1742, 17390, 208608

  1. 208608

  2. 222

  3. 12

  4. 1742

  5. 17390
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The pattern is: ×2-2, ×3+4, ×4-8, ×5+16... (alternating operations with doubling multipliers and powers of 2). Checking: 7×2-2=12, 12×3+4=40, 40×4-8=152 (not 222). The term 222 is incorrect.

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