MHT CET · Maths · Statistics
Mean and variance of six observations are 6 and 12 respectively. If each observation is multiplied by 3 , then new variance of the resulting observations is
- A 288
- B 36
- C 18
- D 108
Answer & Solution
Correct Answer
(D) 108
Step-by-step Solution
Detailed explanation
When each item of a data is multiplied by \(\lambda\), Variance is multiplied by \(\lambda^2\).
\(\begin{aligned}
\therefore \quad \text { New variance } & =3^2 \times 12 \\
& =9 \times 12 \\
& =108
\end{aligned}\)
\(\begin{aligned}
\therefore \quad \text { New variance } & =3^2 \times 12 \\
& =9 \times 12 \\
& =108
\end{aligned}\)
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