A high school marching band has 24% seniors 22% Juniors 28% sophomores and 26% freshmen. what is the probability of a randomly-chosen student being either a sophomore or a junior?

50%

Step-by-step explanation:

24 seniors, 22 junior, 28 sophomores, 26 freshmen = 100

P(sophomore or junior) = sophomore or junior)/ total

                                       = 28+22/ 100

                                        = 50/100

                                           = 50%

the answer is 31.27mph