Can you tell the difference between Coke and Pepsi in a blind taste test? Most p

Question

Can you tell the difference between Coke and Pepsi in a blind taste test? Most people say they can and have a preference for one brand or the other. However, research suggests that people can correctly identify a sample of one of these products only about 60 percent of the time. Suppose we decide to investigate this question and select a sample of 15 college students. a. How many of the 15 students would you expect to correctly identify Coke or Pepsi? b. What is the probability exactly 10 of the students surveyed will correctly identify Coke or Pepsi? c. What is the probability at least 10 of the students will correctly identify Coke or Pepsi?

Explanation / Answer

p = 0.6

n = 15

This is binomial distribution

P(X = x) = 15Cx * 0.6x * (1 - 0.6)15-x

a) Expected value = n * p = 15 * 0.6 = 9

b) P(X = 10) = 15C10 * 0.610 * 0.45

                    = 0.1859

c) P(X > 10) = P(X = 10) + P(X = 11) + P(X = 12) + P(X = 13) + P(X = 14) + P(X = 15)

                    = 15C10 * 0.610 * 0.45 + 15C11 * 0.611 * 0.44 + 15C12 * 0.612 * 0.43 + 15C13 * 0.613 * 0.42 + 15C14 * 0.614 * 0.41 + 15C15 * 0.615 * 0.40

                    = 0.4032

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.