Problem 8. Outdoor Laptop

Durable Devices Ltd. has just completed an extensive survey of all individuals who purchased their popular Outdoor laptop brand. The survey indicates that the time to first failure for this Outdoor brand is normally distributed with a mean of 50 months and a standard deviation of 12 months.

Suppose an Outdoor Laptop owner is randomly selected.

Use StatCrunch to compute the following probabilities, starting with an untitled StatCrunch Datasheet.

a.Find the probability that the time to first failure will be at most 48 months. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 8a. [1 mark]

b.Find the probability that the time to first failure will be at least 36 months. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 8b. [1 mark]

c.Find the probability that the time to first failure will be more than 60 months. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 8c. [1 mark]

Problem 7. Driver phone use

Open a new StatCrunch data table. Suppose that past data indicates that 20% of drivers use a mobile phone on the daily drive to work. For a random sample of 50 drivers (on their way to work), use StatCrunch to compute the following binomial probabilities.

a.Find the probability of getting zero drivers using their mobile phones daily. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 7a. [1 mark]

b.Find the probability of getting more than 10 drivers using their mobile phones daily. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 7b. [1 mark]

c.Find the probability of getting less than 20 drivers using their mobile phones daily. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 7c. [1 mark]

d.Find the probability of getting the majority of the drivers using their mobile phones daily. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 7d.

[1 mark]

e.Find the probability of getting between 5 and 15 of the drivers using their mobile phones daily. Copy and paste the graph and the probability to the Word file Assignment3B under the subheading Problem 7e.

[1 mark]