SOLUTION: The national average for the verbal portion of the College Board's SAT is 507. The College Board periodically rescales the test scores such that the standard deviation is approxima

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Question 86311This question is from textbook modern business statistics
: The national average for the verbal portion of the College Board's SAT is 507. The College Board periodically rescales the test scores such that the standard deviation is approximately 100. Answer the following questions using a bell-shaped distribution and the empirical rule for the verbal test scores.
a. What percentage of students have an SAT verbal score greater than 607?
b. What percentage of students have an SAT verbal score greater than 707?
c. What percentage of students have an SAT verbal score between 407 and 507?
d. What percentage of students have an SAT verbal score between 307 and 607? This question is from textbook modern business statistics

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The national average for the verbal portion of the College Board's SAT is 507. The College Board periodically rescales the test scores such that the standard deviation is approximately 100. Answer the following questions using a bell-shaped distribution and the empirical rule for the verbal test scores.
Assuming you know the 68-95-99 empirical rule you get:
a. What percentage of students have an SAT verbal score greater than 607?
scores of 507 to 607 comprise 34%; Greater than 607 is 50-34 = 16%
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b. What percentage of students have an SAT verbal score greater than 707?
scores of 507 to 707 comprise 47.5%; greater than 707 is 50-47.5 = 2.5%
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c. What percentage of students have an SAT verbal score between 407 and 507?
407 to 507 = 34% + 34% = 60%
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d. What percentage of students have an SAT verbal score between 307 and 607?
scores of 307 to 607 = 47.5 + 34 = 81.5%
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Cheers,
Stan H.