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assuming iq scores are normally distributed, with a mean of 100 and a standard deviation of 15. what percentage of test takers could you expect to score 115 or higher?

User GenesRus
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1 Answer

6 votes

Answer:

16%

Explanation:

1) Mean, u = 100

standard deviation, o = 15

Score specified = x = 115

so, z-score = (x - u)/o

= (115 - 100)/15 = 1

From the probability standard normal distribution curve, 84.13% of the test scores falls within 1 SD (z score = 1), so, the percentage of test scores below 115 is 84.13%, so, for the percentage of test scores of 115 or higher = 100% - 84.13% = 16%.

Therefore, the correct answer is 16%.

User Niraj Chapla
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