Let’s take a second look at the normally distributed IQ scores illustrated in Section 6.1, “Intelligence Scores” (p. 313). If completed, use your Exercise 6.1 solutions as a basis.

a. How is an IQ score converted to a standard score?

b. What is the standard score for an IQ score of 90? 110? 120?

c. What is the standard score for an SAT score of 465? 575? 650?

Using Figure 2.2 on page 314 with the empirical rule:

d. What percentage of IQ scores is greater than 132?

e. What percentage of SAT scores is less than 700?

Using Table 3 in Appendix B:

f. What is the probability that an IQ score is greater than 132?

g. What is the probability that an SAT score is less than 700?

h. Compare your answers to parts f and g with your answers to parts d and e that used the empirical rule and Figure 2.2 on page 314. Explain any similarities.

i. What proportion of the IQ scores fall within the range of 80 to 120?

j. What proportion of the IQ scores exceed 125?

k. What percentage of the SAT scores are below 450?
l. What percentage of the SAT scores are above 575?
m. What SAT score is at the 95th percentile? Explain what this means.