A study considers if the mean score on a college entrance exam for students in 2005 is any different from the mean score of 498 for students who took the same exam in 1975. Let u represent the mean score for all students who took the exam in 2005. For a random sample of 40,000 students who took the exam in 2005, the sample mean, x-bar = 496 and the sample standard deviation s = 100. Report the value of the test statistic.

Kevin has a spinner that has 10 equal sections and 2 sections of each color—red, blue, green, yellow, and purple. kevin spins the spinner 180 times. kevin determines about how many times the spinner will land on red or green, and his work is shown below. -kevin has the formula reversed; it should be the total number of sections over the number of red or green sections. -kevin should have used a 4 in the numerator because there are 2 red sections and 2 green sections. -kevin should multiply by the number of sections in the spinner rather than the total number of spins. -kevin calculated the prediction correctly and did not make any mistakes.