Question

Seventh Grade Students

Instrument # of Students
Guitar 12
Bass 10
Drums 9
Keyboard 12
Eighth Grade Students
Instrument # of Students
Guitar 5
Bass 6
Drums 15
Keyboard 5

Based on these results, express the probability that a seventh grader chosen at random will play the drums as a fraction in simplest form.

Answer 1

3/11

Explanation:

FORMULA= P(A)=

NUMBER OF FAVORABLE OUTCOMES

-------------------------------------------------------------

NUMBER OF POSSIBLE OUTCOMES

GIVEN: 12 Guitars, 10 Bass, 9 Drums, 12 Keyboards

WANT: The probality a seventh grader chosen at randome will play drums

add all the instruments

12+10+9+12=33

there are 9 drums

FOLLOW THE FORMULA

9 3

---- = ---- SIMPLIFIES FORM

33 11