Answer: the probability that a student chosen at random plays the bass is 1/3 in simplest form.
Explanation:
The probability of an event can be found by taking the number of favorable outcomes and dividing it by the total number of outcomes. In this case, we are looking for the probability that a student chosen at random plays the bass.
We know that there are a total of 6 + 4 + 7 + 2 = 19 seventh grade students and 4 + 15 + 13 + 6 = 38 eighth grade students. So there are a total of 19 + 38 = 57 students.
We also know that there are 4 seventh grade bass players and 15 eighth grade bass players, for a total of 4 + 15 = 19 bass players.
So, the probability that a student chosen at random plays the bass is 19/57. This fraction can be simplified by dividing both the numerator and denominator by their greatest common factor which is 19/57 = 1/3.
So, the probability that a student chosen at random plays the bass is 1/3 in simplest form.