d) A score that is 30 points below the mean.2. The Welcher Adult Intelligence Test Scale is composed of a number of subtests. On one subtest, the raw scores have a mean of 35 and a standard deviation of 6. Assuming these raw scores form a normal distributiona) What number represents the 65th percentile (what number separates the lower 65% of the distribution)?
Q. d) A score that is 30 points below the mean.2. The Welcher Adult Intelligence Test Scale is composed of a number of subtests. On one subtest, the raw scores have a mean of 35 and a standard deviation of 6. Assuming these raw scores form a normal distributiona) What number represents the 65th percentile (what number separates the lower 65% of the distribution)?
Understand Problem: Understand the problem and identify the formula to use.We need to find the 65th percentile of a normal distribution. The formula for any point in a normal distribution is:X=μ+Z×σwhere μ is the mean, σ is the standard deviation, and Z is the Z-score corresponding to the desired percentile.
Find Z-score: Find the Z-score for the 65th percentile.Using a Z-table, the Z-score that corresponds to the 65th percentile is approximately 0.385.
Calculate Score: Calculate the score corresponding to the 65th percentile.Plug the values into the formula:X=35+0.385×6X=35+2.31X=37.31
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