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The College Board originally scaled SAT scores so that the scores for each section were approximately normally distributed with a mean of 500 and a standard deviation of 100. Assuming scores follow a bell-shaped distribution, use the empirical rule to find the percentage of students who scored greater than 700.
a. 95%.b. 2.5%.c. 5%.d. 97.5%.

Respuesta :

Using the Empirical Rule, the percentage of students who scored greater than 700 is:

b. 2.5%

What does the Empirical Rule state?

It states that, for a normally distributed random variable:

  • Approximately 68% of the measures are within 1 standard deviation of the mean.
  • Approximately 95% of the measures are within 2 standard deviations of  the mean.
  • Approximately 99.7% of the measures are within 3 standard deviations of the mean.

700 is two standard deviations above the mean. 5% of the measures are more than two standard deviations of the mean. Since the normal distribution is symmetric, 2.5% of these measures are below 300 and 2.5% are above 700, hence option B is correct.

More can be learned about the Empirical Rule at https://brainly.com/question/24537145

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