1) Beneath the graph, label SD and z-scores.
SD
z-score
2) Beneath the graph, label SD and z-scores.
SD
z-score
3) If you have an IQ score of 120, what proportion of the population has a higher IQ than you do?
Note: IQ tests are usually standardized so they have a mean of 100 and standard deviation of 15.
Show all your work, including a clearly labeled graph.
What proportion of the area under the curve is located between
B and C? C and D? A and C? A and B? D and E? A and D?
What proportion of the area under the curve is located between
C and D? B and C? B and D? A and D? A and B? A and E? A and F? C and F?
4) Using the information below, what is the value of zobt?
X = 45 μ = 48 σ = 2
What proportion of scores is below 45? Draw a picture.
6) Your friend tells you she scored 92 on her last exam. You were pretty impressed until you learned that the mean score in the entire class was 95, with a standard deviation of 1.
What is the z-score that corresponds with your friend’s
raw score?
What percentile does your friend’s performance put her
in on this exam?
5) The average person in the U.S.A. spends = 300 minutes watching television each day. Assume that the distribution of television watching is normal with a standard deviation of = 120 minutes.
What proportion of viewers spends fewer than 60 minutes a day watching television?
What percentile is someone in who watches 60 minutes a day?