AP EAMCET · Maths · Statistics
The variance of 20 observations is 5 . If each one of the observations is multiplied by 2 , then the variance of the resulting observations is
- A 40
- B 80
- C 20
- D 10
Answer & Solution
Correct Answer
(C) 20
Step-by-step Solution
Detailed explanation
Variance \(=5\) and \(n=20\) \(\because \quad\) Variance \(=5=\frac{1}{n} \Sigma(x i-\bar{x})^2\) \[ \Rightarrow \quad \Sigma(x i-\bar{x})^2=100...(1) \] Let after multiplication, the new observations be \(y_1, y_2 \ldots y_{20}\) Where \(y_i=2(x i)\) for some \(i\)...(2) New…
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