Consider the discrete random variable X given in the table below. Calculate the mean, variance, and standard deviation of X. Round answers to two decimal places.
\begin{array}{c|c}
X & P(X) \
\hline
1 & 0.68 \
11 & 0.11 \
15 & 0.12 \
17 & 0.09 \
\end{array}
\begin{array}{c}
\mu= \
\sigma^{2}= \
\sigma= \
\end{array}What is the expected value of X ?
Q. Consider the discrete random variable X given in the table below. Calculate the mean, variance, and standard deviation of X. Round answers to two decimal places.
\begin{array}{c|c}
X & P(X) \
\hline
1 & 0.68 \
11 & 0.11 \
15 & 0.12 \
17 & 0.09 \
\end{array}
\begin{array}{c}
\mu= \
\sigma^{2}= \
\sigma= \
\end{array}What is the expected value of X ?
Calculate expected value: Calculate the expected value (mean) of X. The expected value of a discrete random variable X is calculated by summing the products of each possible value of X and its corresponding probability. So, we calculate the mean (μ) as follows: μ=Σ[X∗P(X)]=(1∗0.68)+(11∗0.11)+(15∗0.12)+(17∗0.09)=0.68+1.21+1.8+1.53=5.22
Calculate variance: Calculate the variance (σ2) of X. The variance is calculated by summing the products of the square of the difference between each value of X and the mean, and its corresponding probability. $\sigma^\(2\) = \Sigma[(X - \mu)^\(2\) * P(X)] = (\(1\) - \(5\).\(22\))^\(2\) * \(0\).\(68\) + (\(11\) - \(5\).\(22\))^\(2\) * \(0\).\(11\) + (\(15\) - \(5\).\(22\))^\(2\) * \(0\).\(12\) + (\(17\) - \(5\).\(22\))^\(2\) * \(0\).\(09\) = (\(4\).\(22\))^\(2\) * \(0\).\(68\) + (\(5\).\(78\))^\(2\) * \(0\).\(11\) + (\(9\).\(78\))^\(2\) * \(0\).\(12\) + (\(11\).\(78\))^\(2\) * \(0\).\(09\) = \(17\).\(8084\) * \(0\).\(68\) + \(33\).\(4084\) * \(0\).\(11\) + \(95\).\(5684\) * \(0\).\(12\) + \(138\).\(7684\) * \(0\).\(09\) = \(12\).\(109712\) + \(3\).\(674924\) + \(11\).\(468208\) + \(12\).\(489056\) = \(39\).\(7419\)
Calculate standard deviation: Calculate the standard deviation (\(\sigma\)) of \(X\). The standard deviation is the square root of the variance. \(\sigma = \sqrt{\sigma^2} = \sqrt{39.7419} = 6.30\) (rounded to two decimal places)
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