AP EAMCET · Maths · Statistics
The arithmetic mean of the observations \(10,8,5, a, b\) is 6 and their variance is 6.8 , then \(a b\) is equal to
- A \(6\)
- B \(4\)
- C \(3\)
- D \({12}\)
Answer & Solution
Correct Answer
(D) \({12}\)
Step-by-step Solution
Detailed explanation
Given observations are \(10,8,5, a, b\). Arithmetic Mean, \(\begin{aligned} & \text { A.M. }=\frac{10+8+5+a+b}{5}=6 \\ & 23+a+b=30 \end{aligned}\) Here, \(\therefore \quad \sum\left(x_i-\bar{x}\right)^2=a^2+b^2+93-12(a+b)\) Variance,…
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