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Homework Assignment 5 Name____________________ Note: Show all work. 1. Which of the following is not true of a normal curve? a. It is skewed b. It is a probability distribution c. Its total area contains 100% of the cases d. The mode, median, and mean are identical 2. A _________________ indicates how far an individual raw score falls from the mean of a distribution; the _______________ indicates how the scores in general scatter around the mean. a. standard deviation; z score b. z score; standard deviation c. probability; z score d. standard deviation; probability 3. The equation z = -1.33 indicates that a particular raw score lies a. 1.33 standard deviations below the mean b. 1.33 percent below the mean c. 1.33 percentile ranks below the mean d. 1.33 z scores below the standard deviation 4. The equation P = .33 for obtaining an income between $40,000 and $50,000 represents a. a percentage b. a probability c. a frequency of occurrence d. a z score 5. IQ scores are normally distributed with a mean = 95 and a standard deviation = 12. Based on this distribution, determine the a. probability of IQ scores between 95 and 110. b. probability of selecting a person at random having an IQ between 80 and 110. c. probability of IQ scores between 80 and 120. d. probability of selecting a person with an IQ score below 75. e. probability of selecting a person with an IQ score above 125. f. probability of selecting two people both having an IQ of 110 or above g. probability of selecting a person with an IQ between 105 and 120?