The cost of all maintenance for a car during its first year is approximately exponentially distributed with a mean of

$150.

a. Define the random variable. X = _________________________________.

b. μ = ________

c. σ = ________

d. Draw a graph of the probability distribution. Label the axes.

e. Find the probability that a car required over $300 for maintenance during its first year.

Use the following information to answer the next three exercises. The average lifetime of a certain new cell phone is three years. The manufacturer will replace any cell phone failing within two years of the date of purchase. The lifetime of these cell phones is known to follow an exponential distribution.