Question

A random survey of 30 students found that 17 played a musical instrument. If the school has 450 students, predict how many do not play an instrument.

Answer 1

Given:

A random survey of 30 students found that 17 played a musical instrument.

Total number of students = 450

To find:

Estimated number of students who do not play an instruments.

Solution:

A random survey of 30 students found that 17 played a musical instrument.

Let E be the event that student play an instrument.

So, probability that a student plays an instrument is

`P(E)=(17)/(30)`

Probability that a student do not play an instrument is

`P(E')=1-P(E)`

`=1-(17)/(30)`

`=(13)/(30)`

Now, number of students who do not play an instruments is

`450* P(E')=450* (13)/(30)`

`450* P(E')=195`

Therefore, 195 students do not play an instrument.