What is the value of X in the sequence 20, 10, 10, 15, 30, 75, X?
- A105
- B120
- C150
- D225Correct
Explanation
The pattern in the sequence is that each term is obtained by multiplying the previous term by an increasing factor.
Let's analyze the multipliers:
- 20 * 0.5 = 10
- 10 * 1 = 10
- 10 * 1.5 = 15
- 15 * 2 = 30
- 30 * 2.5 = 75
The multipliers are 0.5, 1, 1.5, 2, 2.5. This is an arithmetic progression where each term increases by 0.5.
Following this pattern, the next multiplier should be 2.5 + 0.5 = 3.
Therefore, X = 75 * 3 = 225.
Option D is 225, which matches our calculated value.
The final answer is D) 225.
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