Multiple choice

Find the missing term in the following series. 89, 71, 55, ?, 29, 19

  1. 38

  2. 39

  3. 42

  4. 41

  5. 43
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The differences are: 89-71=18, 71-55=16, 55-?=14, ?-29=12, 29-19=10. The missing term is 55-14 = 41.

AI explanation

The series is formed by subtracting consecutive composite numbers, starting with 18, then 16, 14, 12 and so on. Subtracting 18 from 89 gives 71, subtracting 16 from 71 gives 55, and subtracting 14 from 55 gives 41. Continuing this pattern, subtracting 12 from 41 equals 29 and subtracting 10 from 29 equals 19, making the correct option D.

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