SOLUTION: The scores for the mathematics portion of a standardized test are normally distributed with a mean of 514 points and a standard deviation of 117 points. What is the probability tha
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Question 1140939: The scores for the mathematics portion of a standardized test are normally distributed with a mean of 514 points and a standard deviation of 117 points. What is the probability that a randomly selected student has a score of 631 points or less on the test? Use the standard normal distribution to estimate the probability. Answer by VFBundy(438) (Show Source):
You can put this solution on YOUR website! The difference between 631 and 514 is 117.
117 divided by 117 is 1. Therefore, a score of 631 is exactly one standard deviation above the mean.
Either by using a z-table or using the 68-95-99.7 rule, the area to the left of the curve from one standard deviation above the mean is about 84%.
So, there's an 84% chance a randomly selected student has a score of 631 points or less.
