Psy
555 Homework 4 Chapter 3 # 1, 2, 3, 4, 6
1. Answer the following questions using the frequency distribution below
(also a) Draw a frequency distribution with this data set.
b) What is the 45
c) What is the 75 d) What is the percent rank for X=5? e) What is the minimum score needed to be in the top 25% of the distribution? f) Is this distribution normal?
2.A population has a m=80 and s=20. Find the z-score that corresponds to each of the following X values (rounding to 2 decimal places, e.g., z=2.25): 85, 100, 120, 75, 65, 60, 130, 82, 68, 80, 105, 30 3. A population is made up of the following scores: 13, 17, 21, 15, 16, 31, 23, 14, 27, 28 a) Compute m and s. b) Find the z-score for each of the raw scores of the population (rounding to 2 decimal places, e.g., z=2.25). 4. For a population with m=85, a raw score of 72 corresponds to a z-score of -1.00. What is the standard deviation of this population? |