JEE Mains · Maths · STD 11 - 13. statistics
If the sum of the deviations of \(50\) observations from \(30\) is \(50\), then the mean of these observations is
- A \(30\)
- B \(51\)
- C \(50\)
- D \(31\)
Answer & Solution
Correct Answer
(D) \(31\)
Step-by-step Solution
Detailed explanation
Given \(\sum\limits_{i = 1}^{50} {\left( {{x_i} - 30} \right)} = 50\) \( \Rightarrow \sum {{x_i} = 30\left( {50} \right) + 50 \Rightarrow \frac{{\sum {{x_i}} }}{{50}}} = 31\)
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