Multiple choice

Find the wrong number in the following number series. 88 44 44 66 130 330 990

  1. 66

  2. 330

  3. 990

  4. 130

  5. Other than these options
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In the series 88, 44, 44, 66, 130, 330, 990, the pattern is: divide by 2, then multiply by 1, 1.5, 2, 2.5, 3, 3.5. Checking: 88÷2=44, 44×1=44 (correct), 44÷2=22 (not 66). Let's try: 88÷2=44, 44×1=44, 44×1.5=66 (correct), 66÷2=33, 33×2=66 (not 130). Another pattern: 88÷2=44, 44×1=44, 44+22=66, 66+64=130, 130+200=330, 330+660=990. The additions double each time: 22, 22, 64, 200, 660. This doesn't work. Testing 130: if 66×2-2=130, then 130×2.5=325 (not 330). 130 breaks the pattern.

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