What is X in the sequence 24, X, 12, 18, 36, 90 ?
- A18
- B12Correct
- C9
- D6
Explanation
To find the logic of the sequence, we look at the multipliers between consecutive terms starting from the known values.
12 times 1.5 equals 18. 18 times 2.0 equals 36. 36 times 2.5 equals 90.
The multipliers are increasing by 0.5 at each step. Following this pattern backwards:
The multiplier before 1.5 must be 1.0. Therefore, X times 1.0 equals 12. This gives X equal to 12.
To verify, the multiplier before 1.0 must be 0.5. 24 times 0.5 equals 12.
The pattern is: 24 times 0.5 equals 12. 12 times 1.0 equals 12. 12 times 1.5 equals 18. 18 times 2.0 equals 36. 36 times 2.5 equals 90.
Thus, X is 12. The correct option is B.
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