Twelve people are given two identical speakers, which they are asked to listen to for differences, if any. Suppose that these people answer simply by guessing. Find the probability that three people claim to have heard a difference between the two speakers.

Probability, P(X=3)=0.05371

Step-by-step explanation:

The experiment consists of 12 Bernoulli trials,n=12

Where sucess is defined with difference between the speakers and failure is defined with no difference between the speakers

Since people are guessing,the Probability P of sucess= 1/2

Therefore P(X=3) = b(3; 12, 0.5) = (12/3) (0.5)^3× (0.5)^9

P( X=3) = 0.0537

answer: a

step-by-step explanation:

9 sandwiches per hour

step-by-step explanation:

when we have a rate, we want a 1 in the denominator

27/3 = 9

27 sandwiches/ 3 hours = 9 sandwiches/hour