Having to do with standard deviation, and percent of scores. Please help me.

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SUMMARY

The discussion centers on calculating the percentage of exam scores exceeding 87, given a normal distribution with a mean of 77 and a standard deviation of 5. To solve this problem, users must utilize the cumulative distribution function (CDF) of the normal distribution. Specifically, the Z-score formula is applied to determine the probability of scores greater than 87, which is essential for understanding the distribution of exam results.

PREREQUISITES
  • Understanding of normal distribution concepts
  • Familiarity with Z-score calculations
  • Knowledge of cumulative distribution function (CDF)
  • Basic statistics terminology
NEXT STEPS
  • Learn how to calculate Z-scores for normal distributions
  • Study the cumulative distribution function (CDF) in detail
  • Explore the use of statistical software for probability calculations
  • Review examples of normal distribution applications in real-world scenarios
USEFUL FOR

Students studying statistics, educators teaching probability concepts, and anyone needing to understand normal distribution applications in exam scoring.

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Homework Statement



The scores on an exam are normally distributed, with a mean of 77 and a standard deviation of 5. What percent of the scores are greater than 87?




Homework Equations





The Attempt at a Solution

I don't understand what it is exactly that I have to do to get the answer. Please Help!
 
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You'll need to use the probability density function or the cumulative distribution function for the normal distribution. Which one?
 

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