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PLEASE HELP!!!

Find P15, which is the IQ score separating the bottom 15% from the the top 85%. Assume the scores are normally distributed with a mean of 100 and a standard deviation of 15.

A. 82.5 B.83.3 C.84.0 D.84.6

PLEASE HELP!!! Find P15, which is the IQ score separating the bottom 15% from the-example-1
User Let
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2 Answers

5 votes

Final answer:

To find P15, which is the IQ score separating the bottom 15% from the top 85%, we can use the standard normal distribution table or a calculator. Since the scores are normally distributed with a mean of 100 and a standard deviation of 15, we can calculate the z-score corresponding to the bottom 15%. The IQ score separating the bottom 15% from the top 85% is approximately 84.46.

Step-by-step explanation:

To find P15, which is the IQ score separating the bottom 15% from the top 85%, we can use the standard normal distribution table or a calculator. Since the scores are normally distributed with a mean of 100 and a standard deviation of 15, we can calculate the z-score corresponding to the bottom 15%.

The z-score can be found using the formula: z = (x - μ) / σ, where x is the score, μ is the mean, and σ is the standard deviation. Plugging in the values, we get z = (x - 100) / 15.

Using the standard normal distribution table or a calculator, we can find that the z-score for the bottom 15% is approximately -1.0364. Solving the equation for x, we get x = -1.0364 * 15 + 100 = 84.46. So, the IQ score separating the bottom 15% from the top 85% is approximately 84.46.

User Muhmud
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8 votes
C .84 because 85 minus one is 84
User Dhooonk
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