Question

Question 3 Coaching companies claim that their courses can raise the SAT scores of high school students. Of course, students who take the SAT without paying for coaching generally raise their scores, too. A random sample of students who took the SAT twice found 427 who were coached and 2733 who were uncoached. Starting with their Verbal scores on the first and second tries, we have compiled the summary statistics in the table below. Try Try 2 Gain (Try 2- Try 1) Coached Uncoached 427 2733 500 506 92 101 529 527 97 101 29 21 59 52 (a) (7 points) Is there good evidence that coached students gained more on the average than uncoached students? (b) (7 points) Is there good evidence that there was a difference in scores on the first try for the coached and uncoached students?

Answer 1

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