Multiple choice

Find the wrong term in the following number series. 7 4 6 9 20 52.5

  1. 6

  2. 9

  3. 20

  4. 52.5

  5. 7
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The pattern is: x0.5, x1, x1.5, x2, x2.5. Starting: 7 x 0.5 = 3.5, not 4. Then 4 x 1 = 4, not 6. If we replace 6 with 4.5: 7 x 0.5 = 3.5, still doesn't work. Testing: 7 x 0.5 = 3.5 (should be 4), 4 x 1 = 4 (should be 6), 6 x 1.5 = 9 ✓, 9 x 2 = 18 (should be 20). If 6 is wrong and should be 5: 7 x 0.5 = 3.5 ✗. If 6 is wrong and should be 4.5: 7, 4, 4.5 doesn't fit. The 6 breaks the pattern.

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