To find the probability that a randomly selected student scored below 73 on the quiz, we need to calculate the z-score for a score of 73 and then find the corresponding probability from the standard normal distribution.
First, we calculate the z-score for a score of 73:
z = (x - μ) / σ
where x = 73, μ = 80, and σ = 8.
z = (73 - 80) / 8
z = -0.875
Next, we look up the z-score of -0.875 in a standard normal distribution table or use a calculator to find the corresponding probability:
P(z < -0.875) = 0.1894
Therefore, the probability that a randomly selected student scored below 73 on the quiz is 0.1894 or 18.94%.
The mean score on a quiz is 80, with a standard deviation of 8. What is the probability that a randomly selected student scored below 73 on the quiz?
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