JEE Mains · Maths · STD 11 - 13. statistics
Let the mean and the variance of 6 observation \(a, b\), \(68,44,48,60\) be \(55\) and \(194 \), respectively if \(a>b\), then \(a+3 b\) is
- A \(200\)
- B \(190\)
- C \(180\)
- D \(210\)
Answer & Solution
Correct Answer
(C) \(180\)
Step-by-step Solution
Detailed explanation
\(\mathrm{a}, \mathrm{b}, 68,44,48,60\) Mean \(=55\) \(a>b\) Variance \(=194\) \(a+3 b\) \(\frac{a+b+68+44+48+60}{6}=55\) \(\Rightarrow 220+a+b=330\) \(\therefore a+b=110 \ldots . .(1)\) Also,…
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