Question

caroline recorded the grade - level and instrument of everyone in the middle school school of rock below.
seventh grade students

instrument	# of students
bass	8
drums	11
keyboard	11

eighth grade students

instrument	# of students
bass	4
drums	11
keyboard	14

based on these results, express the probability that a student chosen at random will play the bass as a fraction in simplest form.
answer attempt 1 out of 2

Explanation:

Step1: Calculate total number of students

For seventh - grade students: \(9 + 8+11 + 11=39\)
For eighth - grade students: \(9 + 4+11 + 14=38\)
Total number of students \(N=39 + 38=77\)

Step2: Calculate number of bass - playing students

Number of bass - playing students \(n=8 + 4=12\)

Step3: Calculate the probability

Probability \(P=\frac{n}{N}=\frac{12}{77}\)

Answer:

\(\frac{12}{77}\)