JEE Mains · Maths · STD 11 - 13. statistics
Let the mean of the data
| \(X\) | \(1\) | \(3\) | \(5\) | \(7\) | \(9\) |
| \((f)\) | \(4\) | \(24\) | \(28\) | \(\alpha\) | \(8\) |
- A \(7\)
- B \(6\)
- C \(8\)
- D \(5\)
Answer & Solution
Correct Answer
(C) \(8\)
Step-by-step Solution
Detailed explanation
\(5=\bar{x}=\frac{\sum x_i f_i}{\sum f_i}=\frac{4+72+140+7 \alpha+72}{64+\alpha}\) \(\Rightarrow 320+5 \alpha=288+7 \alpha \Rightarrow 2 \alpha=32 \Rightarrow \alpha=16\)…
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