In a recent survey, 30 percent indicated chocolate was their favorite flavor of

Question

In a recent survey, 30 percent indicated chocolate was their favorite flavor of ice cream. Suppose we select a sample of 9 people and ask them to name their favorite flavor of ice cream.

a. How many of those in the sample would you expect to name chocolate? (Round your answer to the nearest whole number.)

b. What is the probability exactly five of those in the sample name chocolate? (Round the probability to 5 decimal places and the final answer to 4 decimal places.)

c. What is the probability five or more name chocolate? (Round your probability to 4 decimal places.)

Explanation / Answer

X ~ Binomial (n , p)

Where, n = 9 , p = 0.30

Binomial probability distribution is

P(X) = nCx px (1-p)n-x

a)

E(X) = n * p

= 9 * 0.30

= 2.7

E(X) = 3 (Rounded to nearest whole number)

b)

P( X = 5) = 9C5 0.305 0.704

= 0.0735

c)

P( X >= 5) = P( X = 5) + P( X = 6) + P( X = 7) + P( X = 8) + P( X = 9)

=  9C5 0.305 0.704 +9C6 0.306 0.703 +9C7 0.307 0.702 +9C8 0.308 0.70 +9C9 0.309 0.700

= 0.0988

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

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