Xin recorded the grade-level and instrument of everyone in the middle school School of Rock below. Seventh Grade Students Eighth Grade Students Instrument # of Students Instrument # of Students Guitar Guitar 15 4 Bass 13 Bass 13 Drums 12 Drums13 5 Keyboard 3 Keyboard Based on these results, express the probability that an eighth grader chosen at random will play the drums as a fract simplest form .
The total number of eighth grade students is 31.
The number of eighth grade students who play the drums is 5.
Therefore, the probability that an eighth grader chosen at random will play the drums is 5/31, which cannot be simplified further.