To do these exercises, go to www.macmillanhighered.com/fapp10e.

Question 5.105

2. In Example 19 (page 217), we used the fact that SAT section scores are close to normal and are adjusted so that the mean is close to 500 and the standard deviation is close to 100. (Actual scores in a particular year have a slightly different mean and standard deviation.) Use the Normal Density Curve applet with mean and standard deviation to answer these questions:

  1. What proportion of SAT scores is above 640? (You may want to uncheck the 2-Tail box.)
  2. What proportion of SAT scores is between 420 and 640? (If you drag one flag across the other, the applet shows the area between the flags.)