Multiple choice

In the following number series only one number is wrong. Find out the wrong number. 75 74 146 430 1736 8675

  1. 75

  2. 146

  3. 430

  4. 74

  5. 8675
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The pattern is: ×(position) - (position)!: 75×1-1=74, 74×2-2=146, 146×3-6=432, 432×4-24=1704, 1704×5-120=8400. The number 430 is wrong - it should be 432 (146×3-6=432, where 6=3!). The factorial subtraction pattern makes 430 the clear error.

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