# ch7_practice (1).docx - EDPS 459u2014Ch 7 Practice Name...

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EDPS 459—Ch. 7 Practice Name Karen Gonzalez Finding Percentages with a z Score 1. The average ACT score for 2015 was 20.8, with a standard deviation of about 4.7. Calculate the z scores and find the percentages for the following ACT scores using the z table. i. 32 z = 2.38 What percentage of scores lie below this score? 98 What percentage of scores lie above this score? 2 ii. 23 Z = 0.46 What percentage of scores lie below this score? 66 What percentage of scores lie above this score? 34 What percentage of scores are at least as extreme as this score in both directions? iii. 16 Z= - 1.02 What percentage of scores lie below this score? 86 What percentage of scores lie above this score? 14 What percentage of scores are at least as extreme as this score in both directions? Critical Values, α, p, and Normal Curve 2. Draw a normal curve. Label α = .05 for a two-tailed test . Mark the appropriate z scores for the critical values associated with this α. Shade in your critical regions.