In: Statistics and Probability
Question 37:
The distribution of SAT scores is normal with a mean of µ = 500 and a standard deviation of σ = 100.
What SAT score (i.e., X score) separates the top 25% of the distribution from the rest?
What SAT score (i.e., X score) separates the top 40% of the distribution from the rest?
What SAT score (i.e., X score) separates the top 4% of the distribution from the rest?
Let the random variable X denote the distribution of SAT scores.
Now, we are given that:
Part 1
Let 'a' denote SAT score which separates the top 25% of the distribution from the rest. Thus, 'a' satisfies:
Part 2
Let 'b' denote SAT score which separates the top 40% of the distribution from the rest. Thus, 'b' satisfies:
Part 3
Let 'c' denote SAT score which separates the top 4% of the distribution from the rest. Thus, 'c' satisfies:
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