15% of all Americans have hearing trouble. a) In a random sample of 120 Americans, what...

15% of all Americans have hearing trouble. a) In a random sample of 120 Americans, what is the probability at most 14% have hearing troubles? b) Suppose that a random sample of 120 Americans who regularly listen to music using headphones results in 24 having hearing trouble. What might you conclude?

Expert Solution

(a)

(b)

24 means sample proportion is 24 / 120 = 0.20

Now let us find the probability of getting at least 20% have hearing troubles.

Since above probability is greater than 0.05 so it s not unusual to get a random sample of 120 Americans who regularly listen to music using headphones results in 24 having hearing trouble.

orchestra answered 2 years ago

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