JEE Mains · Maths · STD 11 - 13. statistics
The mean and standard deviation of 100 observations are 40 and 5.1 , respectively, By mistake one observation is taken as 50 instead of 40. If the correct mean and the correct standard deviation are \(\mu\) and \(\sigma\) respectively, then \(10(\mu+\sigma)\) is equal to
- A 445
- B 451
- C 447
- D 449
Answer & Solution
Correct Answer
(D) 449
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & \text { Actual means }=\mu=\frac{100(40)-50+40}{100} \\ & \mu=40-\frac{1}{10}=39.9 \end{aligned}\) Incorrect variance…
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