The mean SAT score in mathematics, mean, is 529. The standard deviation of these scores is 28. A special preparation course claims that its graduates will score higher, on average, than the mean score 529. S random sample of 150 students completed the course, and their mean SAT score in mathematics was 531. At the 0.1 level of significance, can we conclude that the preparation course does what it claims? Assume that the standard deviation of the scores of course graduates is also 28.