Question

10. A tire manufacturer advertises, "The median life of our new all-season radial tire is 75,000 miles. An immediate adjustment will be made on any tire that does not last 75,000 miles." A customer purchased four of these tires. What is the probability that two of the four tires will wear out before traveling 75,000 miles?

11. Explain the reason that the following is not an acceptable probability distribution.

P(X) = 0.25 if X = 1, 3, 5, 7, 9

P(X) = 0.00 Otherwise

12. The total number of heads for a coin flipped four times is a random variable X with the following probability distribution.

P(X=0) = 0.0625

P(X=1) = 0.2500

P(X=2) = 0.3750

P(X=3) = 0.2500

P(X=4) = 0.0625

Draw a graph of the density function.

13. The total number of heads for a coin flipped four times is a random variable X with the following probability distribution.

P(X=0) = 0.10

P(X=1) = 0.40

P(X=2) = 0.20

P(X=3) = 0.10

P(X=4) = 0.20

Determine the mean and variance of X.

Answer 1