First, we need to determine the total number of seventh graders in the School of Rock:
Total seventh graders = Guitar + Bass + Drums + Keyboard
Total seventh graders = 9 + 11 + 9 + 11
Total seventh graders = 40
Next, we need to determine the number of seventh graders who play the keyboard:
Seventh graders who play keyboard = 11
Finally, we can calculate the probability that a seventh grader chosen at random will play the keyboard:
Probability = Seventh graders who play keyboard / Total seventh graders
Probability = 11 / 40
Probability = 11/40
Therefore, the probability that a seventh grader chosen at random will play the keyboard is 11/40.
William 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 9 Guitar 3 Bass 11 Bass 3 Drums 9 Drums 8 Keyboard 11 Keyboard Based on these results, express the probability that a seventh grader chosen at random will play the keyboard as a fraction in simplest form .
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1 answer