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d) A score that is 3030 points below the mean.\newline22. The Welcher Adult Intelligence Test Scale is composed of a number of subtests. On one subtest, the raw scores have a mean of 3535 and a standard deviation of 66. Assuming these raw scores form a normal distribution\newlinea) What number represents the 65th65^{\text{th}} percentile (what number separates the lower 65%65\% of the distribution)?

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Q. d) A score that is 3030 points below the mean.\newline22. The Welcher Adult Intelligence Test Scale is composed of a number of subtests. On one subtest, the raw scores have a mean of 3535 and a standard deviation of 66. Assuming these raw scores form a normal distribution\newlinea) What number represents the 65th65^{\text{th}} percentile (what number separates the lower 65%65\% of the distribution)?
  1. Understand Problem: Understand the problem and identify the formula to use.\newlineWe need to find the 6565th percentile of a normal distribution. The formula for any point in a normal distribution is:\newlineX=μ+Z×σ X = \mu + Z \times \sigma \newlinewhere μ \mu is the mean, σ \sigma is the standard deviation, and Z Z is the Z-score corresponding to the desired percentile.
  2. Find Z-score: Find the Z-score for the 6565th percentile.\newlineUsing a Z-table, the Z-score that corresponds to the 6565th percentile is approximately 0.3850.385.
  3. Calculate Score: Calculate the score corresponding to the 6565th percentile.\newlinePlug the values into the formula:\newlineX=35+0.385×6 X = 35 + 0.385 \times 6 \newlineX=35+2.31 X = 35 + 2.31 \newlineX=37.31 X = 37.31

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