COMEDK · Maths · 29. Statistics
If for a distribution of 20 items, \(\sum(x - 4) = 10\) and \(\sum(x - 4)^2 = 85\) then the standard deviation is:
- A \(1.41\)
- B \(2\)
- C \(4\)
- D \(4.25\)
Answer & Solution
Correct Answer
(B) \(2\)
Step-by-step Solution
Detailed explanation
Let \(y_i = x_i - 4\). Given \(n = 20\), \(\sum y_i = 10\), and \(\sum y_i^2 = 85\). The standard deviation of \(x\) is equal to the standard deviation of \(y\) since it is independent of the change of origin. Variance…
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