These data sets provide the responses of 10 students in class A and class B who were asked how many hours they slept at night. Class A: {7, 6, 7, 8, 8, 7, 4, 5, 6, 7} Class B: {7, 7, 6, 5, 7, 6, 8, 9, 6, 8} Which statement is true for the two data sets?