On May 21, 2004, the National Center for Chronic Disease Prevention and Health Promotion, the Centers for Disease Control and Prevention, reported the results of the Youth Risk Behavior Surveillance€” United States, 2003.The report split the sample of 15,184 American teenagers into grade levels as noted in the table that follows. The students admitted to carrying a weapon within the 30 days preceding the survey and to being in a physical fight during the past year. The following table summarizes two portions of the results.

Does the sample evidence show that students in grades 9 and 10 and grades 11 and 12 have different tendencies to carry weapons to school? Get into a physical fight? Use the 0.01 level of significance in each case.
a. Solve using the p-value approach.
b. Solve using the classical approach.

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At Least Once Never Total Carried a weapon Grades9 and 10 Grades 1 and 12 1,436 1,140 25% 7,008 5,600 2,608 8,444 6,740 15,184 1 In a physical fight Grades 9 and 10 Grades 11 and 12 3,057 1,942 4,999 5,387 4. 798 0,185 8,444 6,740 5,184