The total number of seventh graders is 7+11+12+15 = <<7+11+12+15=45>>45
The number of seventh graders playing an instrument other than guitar is 11+12+15 = <<11+12+15=38>>38
Therefore, the probability that a seventh grader chosen at random will play an instrument other than guitar is 38/45 or 19/23 in simplest form. Answer: \boxed{\frac{19}{23}}.
Lydia recorded the grade-level and instrument of everyone in the middle school School of Rock below.
Seventh Grade Students
Instrument # of Students
Guitar 7
Bass 11
Drums 12
Keyboard 15
Eighth Grade Students
Instrument # of Students
Guitar 5
Bass 2
Drums 12
Keyboard 12
Based on these results, express the probability that a seventh grader chosen at random will play an instrument other than guitar as a fraction in simplest form.
1 answer
1 answer