X is a normally distributed random variable with mean 34 and standard deviation 6. What is the probability that X is between 16 and 52? Use the 0.68−0.95−0.997 rule and write your answer as a decimal. Round to the nearest thousandth if necessary.
Q. X is a normally distributed random variable with mean 34 and standard deviation 6. What is the probability that X is between 16 and 52? Use the 0.68−0.95−0.997 rule and write your answer as a decimal. Round to the nearest thousandth if necessary.
Calculate Z-score for X=16: Calculate the Z-score for X=16.Z=σX−μZ=616−34Z=6−18Z=−3
Calculate Z-score for X=52: Calculate the Z-score for X=52.Z=σX−μZ=652−34Z=618Z=3
Use probability rule: Use the 0.68-0.95-0.997 rule to find the probability.The Z-scores −3 and 3 correspond to μ−3σ and μ+3σ, respectively.According to the rule, the probability that X is within 3 standard deviations of the mean (μ±3σ) is approximately 0.997.
Find probability between 16 and 52: The probability that X is between 16 and 52 is approximately 0.997.
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