Multiple choice

In each of the following number series only one number is wrong. Find out that wrong number. 5 65 715 6435 45046 225225

  1. 5

  2. 65

  3. 715

  4. 6435

  5. 45046
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Series: 5, 65, 715, 6435, 45046, 225225. Pattern: 5×13=65, 65×11=715, 715×9=6435, 6435×7=45045 (but 45046 given), 45045×5=225225. The multipliers decrease by 2: 13, 11, 9, 7, 5. The fifth term should be 6435×7=45045, not 45046. So 45046 is wrong.

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