I need help solving probability problems, especially with the question below.
What is the probability that a randomly selected laptop will be in working condition after 5 years?
What percentage of laptops will last less than 48 months?
If the manufacturer guarantees the laptops for 3 years and will replace if malfunction, what percentage of laptops will need to be replaced?
95% of the laptops will have a life expectancy of at least how many months?
This solution gives the step by step method for computing probabilities based on Z score.