\( X \) is a normally distributed random variable with mean 49 and standard deviation 12 . What is the probability that \( X \) is less than \( 47 ? \) Write your answer as a decimal rounded to the nearest thousandth.
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To find the probability that a normally distributed random variable \( X \) with mean \( \mu = 49 \) and standard deviation \( \sigma = 12 \) is less than \( 47 \), we can use the Z-score formula: \[ Z = \frac{(X - \mu)}{\sigma} \] Substituting the values: \[ Z = \frac{(47 - 49)}{12} = \frac{-2}{12} = -\frac{1}{6} \approx -0.167 \] Next, we look up the Z-score of \(-0.167\) in a standard normal distribution table or use a calculator. The probability corresponding to this Z-score is approximately \(0.433\). Thus, the probability that \( X \) is less than \( 47 \) is around \( \boxed{0.433} \).