AP EAMCET · Maths · Statistics
The mean of five observations is 4 and their variance is also 4 . If three of the five observations are \(1,3,4\) then the product of the other two is
- A 32
- B 36
- C 35
- D 27
Answer & Solution
Correct Answer
(C) 35
Step-by-step Solution
Detailed explanation
\(\bar{x} = \frac{\sum x_i}{n} \Rightarrow 4 = \frac{1+3+4+a+b}{5}\) \(20 = 8 + a+b \Rightarrow a+b = 12\) \(\sigma^2 = \frac{\sum x_i^2}{n} - (\bar{x})^2 \Rightarrow 4 = \frac{1^2+3^2+4^2+a^2+b^2}{5} - 4^2\) \(4 = \frac{1+9+16+a^2+b^2}{5} - 16 \Rightarrow 20 = 26+a^2+b^2 - 80\)…
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