Question 598971
A standardized test has a mean of 600 and a standard deviation of 75. If 1000 students took the test and their scores approximate a normal curve, how many scored between 600 and 750?
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z(600) = (600-600)/75 = 0
z(750) = (750-600) = 150/75 = 2
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P(600< x <750) = P(0< z <2) = 0.4772
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# of scores = 0.4772*1000 ~ 477
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Cheers,
Stan H.