Suppose that the useful life of a particular car battery, measured in months, decays with parameter 0.025. We are interested in the life of the battery.
- Define the random variable. X = _________________________________.
- Is X continuous or discrete?
- X ~ ________
- On average, how long would you expect one car battery to last?
- On average, how long would you expect nine car batteries to last, if they are used one after another?
- Find the probability that a car battery lasts more than 36 months.
- Seventy percent of the batteries last at least how long?
OpenStax Introductory Statistics 2e, 5.3 The Exponential Distribution, exercise 45